As for the keyboard, you could go with any one with midi capabilities to use as a controller. Where the decision will come in will be whether you want weighted keys or not. If that's not an issue, M-Audio and Studio Logic make some good products for cheap. If you do want the weighted keys so that it will feel like a real piano, then it's going to be quite a bit more expensive. I highly recommend looking into the Yamaha P series, which already have some great sounds on them as well.
For sounds, you could go with Reason and/or Sample Tank. Reason is really great because it has a lot of sounds, and you can also record to it, but some of the sounds don't sound all so great. Sample Tank is a plug-in, so you would have to have some other program to record onto, but every sample in it sounds great.
I hope that I was of some help.
) to connect direct in to the computer and record it. what program helps me alter the sound, you know .. giving it a versatile use.