Here's a program to getcha going http://hundredpushups.com/
I think that's a bad program 'cause there is no progression to speak of...it's like you have to jump from easy to hard in like one week. I'd suggest if you want to do alot of pushups start with easy volume like 200 pushups a week. Do these in as many workouts and days you like, and don't care about reps and sets, just focus on the volume, keep the sets easy. Add about 10% to the volume each week. Take rest weeks as you see fit. That's the way I would do it.
1000 pushups with a 100 pound rutsack on. It was punishment from a drill sergeant because some idiot decided to take a cookie from the mess hall before our 3 mile march......
