I'm having the exact same problem. I downloaded a Windows 7 .ISO file from the MSDNAA and burned it on the slowest speed with the disk utility.
Edit: Did find out that when you click repair during the installation you can load the drivers from a dvd. But I'm not sure where to find them on my Windows dvd or how to force exit it and insert the Mac dvd or an external data DVD with the drivers.
Edit2: Worked fine with a different image, go figure