yeah maxtor is the way to go for a ps2 hdd, but Ste! is right you will need a network adapter
search google for a ps2 hdd compatability chart, there are quite alot of them out there
once you have your hdd you will need an os for it, either HD advance or HD Loader, they are the same thing but HD Loader is free from this link, courtesy of stinky_1 afterdawn member :)
yeah... just like the normal sony one, although it won't be recognised by the internal browser like the sony one does... you'l only be able to back up games to it, not transfer save games.
You will be able to save the ps2 games to the hd either through the ps2 if u have the original disk and HDLoader or ur backups with HDAdvance if u use a swap trick or u can transfer ur backups through your pc... then use HDLoader/HDAdvance to boot the games on the ps2.
