I went here to get a manual and I found these downloads: http://www.bossus.com/gear/productdetai ... ductId=174
What are these? Do I need them? I bought my 303 off of Craig's List. The guy wasn't very helpful.

Not unless you're experiencing weird stuff when you use your sampler.

Well, I haven't had the chance to plug my card into my mac to see how it all works. Is that pretty simple? Just get a card reader and the comp will read the files like an external hard drive?
Sorry for asking such (obvious?) questions...I'm strugglin here a bit. Thanks for all your help so far Euclid!

You'll have to have them labeled SMP0001.WAV SMP0002.WAV etc then you can add the files to your card and load them to the 303. You can only load 8 samples at a time and you have to make sure the samples are in 16bit 44.1 khz PCM WAV format.