http://www.ducati.com/my2002/supersport.jhtml
There's the link to Ducati's page that shows all the stuff about the 2002 SS's. You can download the parts catalogues/owners manual/etc. from there, very helpful info to have.

The 2002 900ss's were the first model to come stock with the reshaped aluminum swingarm that is still used on the new 1000ds's. Previously that swingarm was available through Ducati Performance as part of an upgrade kit for other Supersports.

It was also the first year (I think) that 5-spoke aluminum Marchesini's came on the SS. Previously it was the 3-spoke Brembo's.

The 900 is a great engine, and when you figure in the Ohlins shock, adjustable forks, dry clutch, etc., is a really great package and quite an upgrade from the 750.

Nice deal on the bike too! I'd suggest having a dealer look it over to make sure there aren't any outstanding maintenance issues needing immediate attention if there's one anywhere close that you trust. I'm sure you'll love the bike though!!