<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0016 - Disclosure - 9. Notes Payable</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><CurrencyCode /><FootnoteIndexer /><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios><MCU><KeyName /><CurrencySymbol /><contextRef><ContextID>From2012-07-01to2013-06-30</ContextID><EntitySchema>http://www.sec.gov/CIK</EntitySchema><EntityValue>0000098618</EntityValue><PeriodDisplayName /><PeriodType>duration</PeriodType><PeriodStartDate>2012-07-01T00:00:00</PeriodStartDate><PeriodEndDate>2013-06-30T00:00:00</PeriodEndDate><Segments /><Scenarios /></contextRef><UPS /><CurrencyCode /><OriginalCurrencyCode /></MCU><CurrencySymbol /><Labels><Label Key="CalendarSupplement" Id="0" Label="12 Months Ended" /><Label Key="Calendar" Id="1" Label="Jun. 30, 2013" /></Labels></Column></Columns><Rows><Row FlagID="0"><Id>1</Id><IsAbstractGroupTitle>true</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>1</Level><ElementName>us-gaap_DebtDisclosureAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Debt Disclosure [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_DebtDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2012-07-01to2013-06-30" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt"&gt;During fiscal year ended June 30, 2013, the Company repaid
all outstanding notes payable. Notes payable as of June 30, 2012 consist of the following:&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 9pt Sans-Serif; margin: 0 0 0 27pt; text-align: center; color: Red"&gt;&lt;b&gt;&lt;/b&gt;&lt;/p&gt;

&lt;p style="margin: 0"&gt;&lt;/p&gt;

&lt;table cellpadding="0" cellspacing="0" style="border-collapse: collapse; width: 100%; font: 10pt Times New Roman, Times, Serif"&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td&gt;&amp;#160;&lt;/td&gt;&lt;td style="font-weight: bold; padding-bottom: 1pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="3" style="font-weight: bold; text-align: center; border-bottom: Black 1pt solid"&gt;2012&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="width: 70%; text-align: left"&gt;Note payable - Land&lt;/td&gt;&lt;td style="width: 10%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: left"&gt;$&lt;/td&gt;&lt;td style="width: 18%; text-align: right"&gt;200,000&lt;/td&gt;&lt;td style="width: 1%; text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1pt"&gt;Note payable - Other, related party&lt;/td&gt;&lt;td style="padding-bottom: 1pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1pt solid; text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1pt solid; text-align: right"&gt;28,000&lt;/td&gt;&lt;td style="padding-bottom: 1pt; text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Notes payable&lt;/td&gt;&lt;td&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;td style="text-align: right"&gt;228,000&lt;/td&gt;&lt;td style="text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: White"&gt;
    &lt;td style="text-align: left; padding-bottom: 1pt"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;Less current portion&lt;/td&gt;&lt;td style="padding-bottom: 1pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 1pt solid; text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;td style="border-bottom: Black 1pt solid; text-align: right"&gt;(228,000&lt;/td&gt;&lt;td style="padding-bottom: 1pt; text-align: left"&gt;)&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: rgb(204,238,255)"&gt;
    &lt;td style="text-align: left; padding-bottom: 2.5pt"&gt;Notes payable - long-term&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: Black 2.5pt double; text-align: left"&gt;$&lt;/td&gt;&lt;td style="border-bottom: Black 2.5pt double; text-align: right"&gt;&amp;#151;&amp;#160;&amp;#160;&lt;/td&gt;&lt;td style="padding-bottom: 2.5pt; text-align: left"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;



&lt;p style="margin: 0"&gt;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt; text-align: justify"&gt;Note payable &amp;#150; Land at June 30,
2012 consisted of a $200,000 note assumed in the April 2012 purchase of a 160 acre parcel of Colorado land referred to as Indian
Mesa. The note, due to Indian Mesa, Inc., a previous owner of the land, is secured by the land, is non-interest bearing, and was
due on November 15, 2012. Due to the short term nature of the note, no interest rate was imputed. The note was repaid on the scheduled
due date.&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt; text-align: justify"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt Times New Roman, Times, Serif; margin: 0 0 0 27pt; text-align: justify"&gt;Note payable &amp;#150; Other, related
party, at June 30, 2012, represents an unsecured convertible note due to the Company&amp;#146;s Chief Financial Officer. The note
was a 10 day demand note in the amount of $28,000, bearing interest at 8% per annum, issued for additional working capital. The
note was convertible into Class A Common Stock at $2.24 per share. Related interest expense for fiscal 2013 and 2012 was $2,300
and $1,700, respectively. The note and accrued interest were paid in full prior to June 30, 2013. See Note 13 &amp;#150; Related Party
Transactions for additional information.&lt;/p&gt;

&lt;p style="font: 8pt/15pt Times New Roman, Times, Serif; margin: 0; text-align: justify; text-indent: 0in"&gt;&lt;b&gt;&amp;#160;&lt;/b&gt;&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 505

 -SubTopic 10

 -Section 50

 -Paragraph 3

 -URI http://asc.fasb.org/extlink&amp;oid=6928386&amp;loc=d3e21475-112644



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher SEC

 -Name Regulation S-X (SX)

 -Number 210

 -Section 02

 -Paragraph 19, 20, 22

 -Article 5



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 210

 -SubTopic 10

 -Section S99

 -Paragraph 1

 -Subparagraph (SX 210.5-02.19,20,22)

 -URI http://asc.fasb.org/extlink&amp;oid=6877327&amp;loc=d3e13212-122682



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