Here's the link, fixed up:
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=3855596229&ssPageName=STRK:MEWA:
%20IT
Well, 1 HP = 746 Watts, so this motor was rated to provide a max of about 2200 Watts output. That rating is derived from the formula HP = (Torque * RPM) / 5252 so at some sweet-spot along the whole range of speeds this motor can run, the HP peaks out at 3.
The 320 Volt max rating should probably be view seperately from current. It is probably more a reflection of the insulation class of the windings. The 212 A current rating is probably a max rating the windings can take (likely to be briefly) before melting.
I'd say that motor would have been a good choice for a gen, though it'd prolly need gearing up for wind apps. However, you couldn't expect to get more than about 2kW from it (prolly a lot less).