You may have not fried anything. The loud clacking sound you heard was probably the starter relay chattering because there was not enough current to activate the bendix. Yeah, there should have been plenty of current with the jump-start, but you did mention moving the ground cable. I'm not so sure the problem lies in your starter -- the symptoms may point to a current drain that is depleting the battery, or perhaps your battery merely will not hold a charge.
As in all repairs, do the easy stuff first. Remove the battery and have it load-tested. If you're looking at making electrical repairs/replacements (i.e. brushes for the alternator, new rotor, blah blah blah...), check out www.motoelekt.com
-- the owner is very helpful with troubleshooting if you don't have a local guru.