This time of year, you are kind of limited because most of the bare root sellers have finished shipping. Edmunds sends good sized bare root plants and they are still shipping. Jackson and Perkins is still shipping bare roots, as are the other companies affiliated with them. YMMV with them.
As far as potted roses go, I agree with the others- High Country, ARE, A Reverence For Roses are all pretty reliable. ARE sends great big beautiful potted plants but you pay for shipping that dirt.
I would love to be within driving distance of Roses Unlimited. Of course if I were, I would also be wishing for a really big truck to haul the roses home.
For really good roses, wait until September and order from Palatine in Canada. Regan sent me good looking roots this year too, and as Amanda said, they start taking orders in JULY for shipping next February!
One more...amazingly, Home Depot's bagged roses this year have real nice roots on them, and they have some newer ones such as Francis Meilland, Canyon Road, Brick House.