If you need a cheap PDA all you have to do is check out EBAY for the PDA you want and if you see the auctions for it end up past $100 budget, then look for a slightly older PDA and see if you can get that one for $100. Does your PDA have to be be palm or what? If you get a pocket pc 2002 which should be fairly cheap now, I'm pretty sure that would be sufficiently fast for what you need it to do.