Should I panic? Bike not serviced in 4 years / 3500 miles...

[Lukey]

Thanks everybody for the advice!  I now know that it's not something to take my chances with.  I'll get the belts and oil done ASAP.  As for the gas and tires, they're okay.  As one of you suspected, the bike has been ridden regularly, just not a lot.  I bought it a few months ago from someone who had two bikes and just wasn't putting the miles on the Monster.

Where can I find info on doing the belts myself?

[Grappa]

 http://www.ca-cycleworks.com/videos/  if your bike is a 2V.  Also you could get a Haynes Manual for belts and all sorts of other maintenance.   

[Howie]

This one also:

http://www.ducatisuite.com/beltchange.html