IIRC, Cave Spring and Pine Flat are NFS campgrounds on rte 89A north of Oak Creek, right? Both are very pretty, being right beside Oak Creek, but the one that is a couple miles north of the other is prettier and more desireable, in my opinion. Both have relatively small sites, as Bob mentioned, but not side-by-each as in commercial campgrounds. Both require reservations, though that shouldn't be a problem in April. Both are dry, with central water faucets, central bath houses, and a dump station. The interior roads are paved but narrow, and backing into some of the sites is a challenge. Both campgrounds have trails going through them for casual hiking, and are near trailheads for more serious hiking. See
http://www.go-arizona.com/Cave-Sprin...t-Campgrounds/
if you haven't already.
There is a commercial campground with hookups at the south end of Schnebly Hill Rd, just off rte 179 in Sedona - just opposite Tlaquepacque Village. Called Rancho Sedona, if I recall. Easy to get to, nice setting right against the creek, central to everything, but a bit crowded. Schnebly Hill Rd is a fun drive in itself - a winding dirt road. There is a trail running parallel to it that is great to hike. And at the north end, you are back at I-17 south of Flagstaff. Beautiful country!
You'll have a great time in any of these.
Bill