I know that alot of these selling on ebay are refurbished units and they sell for quite low. A supplier I know of that has some good prices is Link hidden: Login to view but you have to register with them to see thier wholesale prices. The main site is thier basic prices.
Quote from thier wholesale section
Myworld Phone is the leading distributor of GSM Mobile phones in the USA and Canada. For Wholesale purchase please follow the simple process. Our company is dedicated to service brokers, importers, resellers and retailers who are looking for wholesale deals on GSM phones. Under one roof you will find 512 different models of GSM phones and over 4,000 different accessories at our stock. We have the lowest price and the highest quality products manufactured by name brands such as Motorola, Nokia, Sony Ericsson, Panasonic, LG and Apple computers inc.