I've gone to the spring show for over 12 years and it is always wonderful. Lots of beautiful quilts, great stimulation and, of course, lots of vendors with all the new things. As has been said, hotels book up a year in advance although you can sometimes get "lucky" with late openings when tours don't fill up.
This year I'm checking out the fall show and hotels are all nearly booked for that one as well.
Hope you enjoy the show - just bring your walking shoes as the whole town is involved with vendors spread at the convention center and downtown as well as spending time at the National Quilt Museum.