I should probably add this to the package but I'll just post it here now for your benefit.  This page sends the email when you click the send button:

 

The Visualforce page:

 

<apex:page standardController="Quote__c" extensions="QuoteEmailPdfExt">
<apex:form >
<apex:pageMessages />
<apex:commandButton value="Send" action="{!sendQuotePdf}"/>
</apex:form>
<apex:outputPanel rendered="false">{!Quote__c.Contact__c}</apex:outputPanel>
</apex:page>

 

The Apex class:

 

public class QuoteEmailPdfExt {

public Quote__c q { get; set; }

public QuoteEmailPdfExt(ApexPages.StandardController controller) {
q = (Quote__c) controller.getRecord();
}

public void sendQuotePdf() {

EmailTemplate t = [select id from EmailTemplate where DeveloperName = 'Quote'];

Messaging.SingleEmailMessage m = new Messaging.SingleEmailMessage();

m.templateId = t.id;
m.targetObjectId = q.contact__c;
m.whatId = q.id;

Messaging.SendEmailResult result = Messaging.sendEmail(new Messaging.Email[]{m}).get(0);
if(result.isSuccess()) {
ApexPages.addMessage(new ApexPages.Message(ApexPages.Severity.CONFIRM, 'Email sent :)'));
} else {
ApexPages.addMessage(new ApexPages.Message(ApexPages.Severity.ERROR,'Whoops: ' + result.getErrors()));
}
}

}

 

 

If you want to put a button on the quote page that does this automatically then update the page above to bind the page's action attribute directly to the sendQuotePdf() method and then create a custom button on Quote that uses this page. 

 

You'll also want to modify the page to remove the button, obviously, but don't remove the pageMessages component as it conveys the success/error messages as appropriate.