Don't stay at a hotel. There are several RV/campgrounds that rent out small cabins that have all the amenities for almost half the price.
I've stayed here and enjoyed it very much. http://moab-utah.com/moabrim/
$49 split two ways a night is a steal. Shower, kitchenette, microwave, queen size bed, and a set of bunch beds.
The Moab Diner has some awesome green chili.
You can find the book Jeff mentioned in about every shop or gas station in Moab. As Jeff said, it's pretty good even though I've found some errors in it.
May can still be chilly weather wise so make sure you take some warm clothes.
Trails I recommend:
7 Mile Rim
Fins & Things
The Safari normally goes to this Potato Salad Hill (video at the top of page)
Hey Joe Canyon (not difficult but scenic)
This was last years trip
This years trip. The first couple sets of pics in this album are actaully from Colorado. The DCLB with the besttop is Jeff's.