If I were to do it all over again, I'd only buy gear used. Except the helmet, which you should buy new. The latter is like buying underwear: you don't know where its been or what's been done to it. The rest is less relevant in terms of wear.
Another great part about starting with a 250 is sheer cost. It will be less money up-front, less in insurance, awesome gas mileage (50+ IIRC). And they hold their value very well. Supersports just don't because they're getting totaled all the time.
Anyway, used gear sources: Any major bike forum (gixxer.com, 600rr.net, WERA classifieds, kawiforums.com, sporbike network, and others) as well as locale-specific forums that you'll have to discover with a google.
EDIT: Duh, Craigslist can be good if you're near a larger city. I'm less about Ebay but I HATE Paypal and the way it is run, so its a personal bias.
Dragging knee is for the track, and dragging tail is for the lot. --Kane Friesen
When you're in a car, you're watching a movie; when you're on a bike, you're in the movie. --Robert Pirsig
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