Braking System (in most states, it's the law)
Detachable towing lights (optional, some use, some don't)
We have the Roadmaster Falcon All Terrain tow bar set up & a Classic Brake Buddy. It's been a while since we bought ours, but I think it was about $700 or so for the tow bars & $1200 for the BB. I don't remember what labor was (we had dealer install the Roadmaster), but probably ran a few hundred dollars.
Although you have a 2002, Motorhome Magazine's 2010 Dinghy Guide
has a lot of information on what you need to know before you tow (something previous versions of the guide did not have). It is suggested reading, especially since you are new to RV-ing.