If you can find a cooperative dealer, you can put your coins on sale on a consignment basis. This is good for the dealer because he doesn't have to invest the capital to buy your coins before he can make a profit off of them. Be sure that you set a minimum amount that you are willing to sell the coin for, as if you do not, the dealer will still make a percentage profit selling it for less than its full value. Remember that with consignments, dealers make money off of moving the maximum number of coins. Unlike an auction, you might sit on the coin for a long time before it sells.
Classifieds Selling coins via the classified section of a numismatic newspaper is another option.
However, this is viewed with enough suspicion that you may have to set the price fairly low for someone to take the risk of sending you the money. Fortunately, there isn't a lot of abuse of this type of system, and there are a lot of honest people out there. This carries with it some of the risks of being a dealer. For example, if the coin is counterfeit, you could conceivably get into trouble and might have to buy the coin back. Online classifieds are perhaps even more risky in that their is not normally a mechanism for reporting abuses in the system as there is with most newspapers.