I sold for a while on eBay and while my experiences were all positive I would suggest that you do not make eBay and PayPal your sole source of revenue.
Paypal can freeze your account at any time for any reason. This can create a death-spiral for a small business owner.
My products were for a niche market so the risk of being scammed was very low. However, there are certain categories that scream scams such as clothing, jewelry & accessories (especially women's hand bags).
Go to eBay and click on the community link (now at the bottom of the page) and go to Discussion boards. The seller central, part time sellers and paypal forums would be a good place to ask questions.