Originally Posted by HillRider

Depends on where you order them. If you want your LBS to build them then it's not nearly as attractive as going to a large retailer like Colorado Cyclist or Excel Sports.

Your LBS gets his parts wholesale (or at least at distributor cost), which is better than you can do as an individual, but they only order a few sets at a time. CC, Excel, etc, order hundreds or thousands of rims and spokes at a time. It's obvious who has the better cost structure and who can sell for less.