The alternate P90X routines I've created can be viewed here.

The core routine is one I found on the interweb, and it's here..

Just a disclaimer. I'm by no means an expert, and it's a total work in progress. It really just started off as me cobbling together dumbbell exercises.

The PDF's here are my latest incarnation, but I may think one particular exercise is out of place in the middle of my workout, and I sub in another exercise on the fly. That's the cool thing about all of this...I've been doing P90X for so long, and now I'm learning how to exercise in a whole new way.

Regarding Chest and Back:

For any dumbbell press variations, I just lay on the floor. I don't use a bench. For incline presses, I lean a 1x8x4 piece of lumber I got at the Home Depot against a chair at the desired angle

I kept half the push up exercises, but rather than crank out 30 plus on each set, I shoot for 20 reps in a slow, controlled motion. (1 second down, one second up), and I get a serious burn going.

Still kept the pull ups, but again, I use a dip belt to add weight. Prior to adding weight, I was doing 12-15 reps on each pull up exercise.

I've only added 10 pounds to the dip belt, and now I do 8 reps, and concentrate on good form. I didn't know how much I was kipping until I started using the dip belt, and the damned 10 pound plate kept hitting me in the shins because of all the swaying I was doing during my pull ups. Once I can do 10 reps for each set during a routine, with good form, then I'll add weight to the dip belt, and start the process all over again.

Hope this helps.