Just wanted to give Marah's Elegant Bridal in Mount Horeb (about 15 minutes from the far west side of Madison) an *excellent* review.
I visited Marah's in December after a friend recommended her shop. While she doesn't have a huge selection (I would guess maybe 50 dresses or so), they are all hung on the rack for you to browse. She carries a few dresses by Enzoani, Essence of Australia, and Casablanca. Her shop is adorable, the service is amazing (I went on a Saturday morning and it was just Marah & I in the shop...granted this was a slower time of year, but still nice). Marah knows you by name and is incredibly helpful when it comes to advice on accessories and various wedding questions. Best of all, she is honest about what looks good on you. She said all of her dresses are under $2000, with the average price being around $1200. She also carries Meg Jewelery, a semi-exclusive brand of handmade jewelry that is also sold at Kleinfeld's. Marah recommends a seamstress in Waunakee, WI for her alterations, keeping the customer's price down (around $150 for alterations).
I also looked at Vera's in Madison, but had a much better experience at Marah's.