The NC State University and the RBC Center are both nearby so you may also wish to search for motels near those locations. Historically some nearby motels have offered discounts for RARSfest or other NC State Fairgrounds visitors but every year seems to be different so you need to ask about discounts when making your reservatioins.
Hotel Guides also lists motels near the NC State Fairgrounds (Just south of the PNC Arena).
Here is a Travelocity listing of motels near the NC State Fairgrounds.
More locations and prices throughout Raleigh can be found on the Visit Raleigh web site.