hi im completely new to mac and know very litle about them except they work and do their job better than pc's. ok my beef is im going to purchase my first mac at then end of next month used from a good buddy of mine for $200 and the touch pad dosnt work. is there a way to fix it? he is however giving me a mouse with it so i can still use it. he got it from a pawn shop for around the same price. everything else as far as i can tell works fine on it. except its kinda slow. also can i intsall an airport card on it or is that only g4 i books? if i cant would i be able to buy a mac compatible usb wifi device?