Ebay is an easy way to get stuff cheap, once you learn the ins and outs. It sounds silly but if you're having trouble winning anything on ebay, I suggest a tutorial on the site. They give you the basics, which, once you've gotten a grasp on those, winning becomes much easier. I always decide the most that I'm willing to pay for something (including shipping) and make that bid. If I can actually be online for the auction's end, I'll actually wait to bid until the last 20-10 seconds (also known as sniping). If I don't get it, someone else can have it. I had my highest price I was willing to part with and someone else had something higher. I'll find another one later.
Anyway, I could go on and on, but I think you get the idea...
-Jason