First let me give you some advise based on your post. If you go to Mexico (Baja) don't go there with a gun, don't go there with drugs and leave your bad attitude and heavy drinking (if you do) at home. You can get into some ugly trouble if you think it's a good place to party hardy.
I say this all because I have been going to Baja since 78 with all the off road races. It's an adventure every time I go and I have a million stories. If you are looking for long ride, unbelievable sights and neat people, Baja is a good choice. There is technique in dealing with the authorities and this needs to be addressed before you go.
As for the tours, Cycle News has tours listed in their ad section. I would recommend Chris Haines who is a Baja racing champion and runs many tours.
If you want more info, E-mail me.:cool: