SukhDee,
I've been using a strictly ACID/Cool Edit setup for 5 years now, got my MPC and a Yamaha A4000 a few weeks ago, and I've been experimenting with the best ways to integrate my old ways of working with my new hardware.
First, IMHO ACID 4.0 is an awesome tool if you take full advantage of it. It seems really simple at first, but if you're patient you can learn to do a lot with it, and you probably can work a lot faster than you can w/ hardware. You can create all kinds of crazy effects envelopes, route your effects and tracks to busses, and create effects envelopes on the buses. Very, very flexible.
One of the many things I'll do w/ drums in ACID is take a break, zoom in all the way on each individual beat (you can see the zero crosspoints pretty well enough), and line each beat up with ACIDs sequencing grid. Then render the loop to a new wav, and if there's any clicking due to my cutting I'll clean it up in CoolEdit.
If you just want to straight-up extract the beats from a break, though, then ACID probably isn't your tool. CoolEdit is OK - use the Edit -> Auto-Cue -> Find Beats and Mark feature. It lets you snap to the beginning of each beat, but I find it's not always reliable.
What HybridBeats.com said was right on the money - for just extracting individual drum samples, Propellerhead's Recycle is the tool. It will autofind the beats for you, export them each to their own wave file, and then you can export them to your MPC. I haven't done this yet (I don't have recycle yet), but it supposedly will also create a .mid file containing the starting position of each of the drum hits in the original break, and you can change the name to a .seq file, export it to your MPC and recreate the original break on the MPC. This is a very flexible approach because you can change the bpm of the sequence without distorting the break or changing the relative timing between hits. Check out the following tutorials for more info:
http://www.mpc-tutor.com/tutorials/recycle.php
http://www.mpc-tutor.com/tutorials/recycle2.php
Alex