There are several viable options, I guess it depends on how quickly you're looking to sell. There's always EBAY but I try to use them as a last resort. There's local coin clubs in your area, Craiglist, flea market dealers, coin shows or coin stores (although they won't offer you a fair market value like a private collector likely would). Depends on how patient you're willing to be I suppose. What sorts of coins are you looking to sell if I may ask?
Before being able to direct you to a good place to sell, it would be important to know what you plan to sell. Is it high end? Average? Low end?
The majority of the coins I'm trying to sell are silver Washington quarters and silver Roosevelt dimes, but there are also a number of other coins including Morgan silver dollars, buffalo nickels and a couple of large cents and half dimes.
So I realize I'm not an expert nor am I touch on every possible sales platform here, but here is some of my experience and perception... A LOT of people bemoan Ebay for its fee heavy platform. But here's the deal, in my experience, if you sell it it's a done deal. I like that aspect. I have tried Craigs list, E-crater, etc...and while it gets your stuff out there it doesn't draw near the crowd of serious buyers that ebay does. When someone buys your item for the most part you're getting paid. Your market of serious buyers instantly shrinks when you go away from Ebay. So if you've bought right you should be able to sell on Ebay with no problem. Now I understand if you aren't buying to sell, which most collectors aren't, then you may take a loss on Ebay, so in that regard Ebay may not be the answer. But, IMO, just like with coins, you get what you pay for. There is a reason Ebay charges those fees. Not to mention all the tertiary things you get with ebay, including your feed back scores and other things that you would other wise have to manage yourself. My experience with Craigs list can be summed up by this story. I've had a tool box full of tools in my garage for sale on CL for over 4 months. I feel its fairly priced and I am open to offers. To date, I've been contacted 5 times all with offers and *NOT ONE* of those offers has panned out and I've said *YES* to every offer. In fact, 4 out of the 5 never replied to my email accepting their offered, the 5th gave me an offer me on a Friday, i accepted, set up meeting time and date for Monday and the guy never showed. To me CL has become a place for hustlers and hagglers who are trying to get rich quick. So it tends to attract more of a less serious buying\bartering crowd. While I've successfully sold a hand full of items on CL, and have learned to enjoy the haggle, its become less and less dependable and consistent. Now, if you are just wanting to sell your silver Washington quarters and silver Roosevelt dimes because you bought them as part of your collection and are now trying to sell to free up money for a different collection purpose your best bet is going to be finding a collector who wants them. A coin shop, IMO, is no different than E-bay in that with E-bay you have fees that may cause you to sell at a loss, a coin shop is certainly not going to give you top dollar because they need to resell. So if you have to sell with out a loss, then your best bet is a collector or a local club. Another option might be to use Craigs list and offer a trade or find local collectors who have what you want and trade them.