Re: Alesis Sample Pad
I don't download sounds, but I know there are sites out there. But if you're not 100% comfortable with them, simply don't click on anything.
There are all types of sample discs available, some as little as $10 or less, and some feature a number of the classic machines like Roland, Linn, Oberheim, etc. Sometimes the files are .wav format, sometimes they're audio CDs, which means you'll need to extract (rip) the sounds and save as .wav files. Those will probably be your best way to get a large number of sounds without a lot of fuss.
You may also find other players willing to swap/give samples from their libraries.
And, you can often grab sounds from existing CDs, but again that means ripping them and editing in an editing program.
It's possible to grab sounds from other machines if you simply record their output into an audio editing program.
Now that I've mentioned it 3 times, I think that's your first step - get an audio editor. I use Sound Forge, but it's certainly not free. I think free programs like Cool Edit are still around, or you can try Office Depot/Staples for their $10 software selection, probably something in there.