According to Edmunds, the invoice for a base Tacoma with auto is about 15K:
http://www.edmunds.com/new/2009/toyo...38/prices.html
Average buying price shows at 16,100 (after delivery etc), but that's the average, you can do better. Start from invoice and work up, don't go from MSRP down as they would have you do. $15,500 maybe - you'll do well to stay in that range, paying cash will help you since you don't have to worry about approval, etc.