hmmm.

First up i suggest finding the weirdest cds you have lying around the house, ripping some tracks to audio using freerip (http://www.mgshareware.com/frmmain.shtml) , and then using an audio editor like audacity (free also) (http://audacity.sourceforge.net/) to cut loops and hits out of them. I'm not advocating thieving peoples samples but its probably the best place for you to start off.

Couple of things to watch out for. When you have found a sample you like and cut it out you have to make sure the start and end of the sample hits zero as if its off youll get some crappy clicking and clipping noises when you try to loop it or play it. Select the first few ms of othe file and in your audio editor their should be a fade in option. Fade the ****er in. Then select the last few millisecond of your sample and do a fade out. You may also want to normalise the whole sample, which will bring the volume of the sample up to its highest level without clipping the signal. The normalise function is standard in all audio editors so have a look around for it. Remove the DC-offset too and this reduces headroom (usually only applicable to sounds which been recorded with you line in\mic etc, but you may as well do this consistently on all you samples).