See if you can find anyone in this thread who can repair hardware close to you. You don't mention where you're from so I can't be more specific (maybe you could enter your location in your profile).
http://www.amiga.org/forums/showthread.php?t=53964Which disk are you inserting into the A2000? Is it Amiga-formatted, like a Workbench disk, or is a blank or IBM-formatted floppy? If it's a blank, try formatting it from Workbench and see if it creates a new, usable disk (usually called Empty unless you label it). If it's a game, which sometimes aren't readable from Workbench, try rebooting your Amiga with the disk in the drive and see if it boots from it.
Good luck with your Amigas, I hope you get them up and running again!