tip:

do not bid until teh last second, bidding early only increases the bid price. (aka bid sniper)

beware of sellers over charging for shipping, there are many sellers out there so don't rush into bidding on an item

beware of buying insurance on shipping...especially if they use UPS. remember that UPS automatically insures everything up to $100 so you buying insurance for something <100 is giving away free money to the seller.

make good use of teh "completed items" link so you know what the ebay market value is for the item you are bidding on

most of all have fun!! I've found some good deals on ebay and also sold a few items myself like bobbleheads and even my civic