Oh yeah! Ebay is great. You need to be careful though....don't get caught up in the excitement of the auction and pay more for something than it's worth. I have been on it for about 4 or 5 years now and see it happen all the time. I see far too many people get excited and pay more for something than you could buy it new for. I have also gotten some outstanding deals.
You can sell ANYTHING on ebay. There is always someone out there waiting to buy what you have.....no matter what it is. Type in keywords like smelly, nasty, booger, poop, etc..... you'll be surprised at what people are bidding on.
If you plan on selling more than a couple items, get a PayPal account. Personally, I won't even bid on something that I can't pay for with Paypal. It has to be rare or I need it desperately before I will fool with a money-order. I know many other people that are the same way.
If you are selling smaller items, get a kitchen scale from wally-world. You can find shipping costs online. I think USPS priority for under 5lbs is 3.95 anywhere in the 48. Include the charges in the auction ad. Some sellers do not put anything in their ads and then when it's over they will tack on an outrageous amount for "handling charges." These are ok, just don't over-do it.
If you have a quantity of an identical product, don't sell them one right after the other. You'll flood the market and after the first one or two you won't get squat from the rest. I bought some high dollar tools from a guy that made the mistake of putting in his ad that he had a whole bunch of these from a factory that closed. After the first few sold for nearly 75% of original price I got mine for 5% of original. I bought 3 of them before the guy caught on.
Have fun!