Today’s eBay is a mix of new and used merchandise sold by individuals and businesses. Collectors of antiques will still find plenty, but there are even more cars, cameras, clothing, and computers.

To join, you must be at least 18 (younger with parental consent), and you must provide your name, address, and phone number.

You search for what you want by category (sports memorabilia, say), subcategory (bobblehead), or name (Lou Gehrig). You can create a page that automatically keeps a cybereye peeled for new auctions of items in which you’re interested. Tutorials take you through the bidding and selling process.

There are three ways to buy: Bid in an auction--scheduled for one, three, five, seven (the most common), or 10 days; click on Buy It Now to purchase an auction item immediately at a set price; or opt for Fixed Price, which doesn’t involve an auction--you buy as if in a store. Fixed Price works well for goods whose value you can easily gauge (computers, for example).