After reading 'bc's Follow-up, I'm more inclined to go with his number. $40 per square seems a bit low anywhere you go.
In any event, what you could do is see if you can get an estimate for the STANDARD roof your builder is proposing. Then, from the same contractors, get another estimate for what YOU want. Obviously, Estimate #2 - Estimate #1 will tell you if $2200 if too much. Will your builder let you put on your OWN roof? ANd if so, how much of a credit will you get? With this amount, then get some contractors to bid the job. With this, and the builder's credit (assuming he'll give you one), you'll have your price.
Check this out - Wholesale Roofing. Maybe they can help. Consider having someone take a picture of the house from a few angles with a digital camera, and e-mailing them to a place or 2 on the WEB. As long as the roof can wait, what have you got to loose?