I don't know of any RV parks actually in Raleigh. The NC fairgrounds in Raleigh offers full hookups for $25 a night and is in a good location (for us, anyway)
NCDA&CS - N.C. State Fair Division
Follow the instructions given on the web site; pick a spot and call Security on your cell phone and they will come out and register you. If you need help finding a spot, call Security first and they will come out and assist you. We have camped there a couple of times and truthfully, the security people are friendlier than a lot of campground owners!
Unfortunately the fairgrounds don't do you much good right now as the State Fair is on Oct 15 - 25