man...those buggers are a pain in the arse....had to do it to a car CD player once.....never again!
If you're not proficient with a pencil tip iron and that switch is mounted to a tiny PCB, you will likely knacker up the replacement. Other wise, you will likely have to dismantle a portion of the drive tray housing and tracking just to get to the darn thing. Then if it's a standalone switch mounted to the track housing by micro screws, you have to find a switch with a similar enough mounting template--you probably won't find this at the local Radio Shack.
Seriously, go to Wal-Mart and get a new one--they're dirt cheap now. And you won't waste a whole evening tinkering with it only to fek up even more in the end.
If it ain't broke don't try to fix it! But, hell if you can tweak that bastard just a little bit more....hehehe.