I actually started my invoicing life with Zoho Invoice. They have since become available on Google Apps, which is super convenient for me, as a Google Apps user

I actually started my invoicing life with Zoho Invoice. They have since become available on Google Apps, which is super convenient for me, as a Google Apps user: http://www.zoho.com/invoice/zohoinvoice-for-googleapps.html http://www.zoho.com/invoice/zohoinvoice-for-googleapps.html