If they're slabbed, Heritage, Teletrade or Great Collections. If they're not, Craigslist or a local shop. Heritage tends to be higher end coins, TT and GC are a little bit of everything. And no matter where you sell, you'll get only what the coins are worth, and with the exception of Craigslist, you'll be paying someone something to sell your coins.
Prices vary wildly on eBay... for example, the completed listings for a '14-D Lincoln cent in VF show a price swing of $117 on the low side and $285 on the high side. http://www.ebay.com/sch/i.html?LH_S...omplete=1&_nkw=1914-d+vf+lincoln+cent&_sop=15
Common, raw circulated coins, assuming these are raw and circulated, are best sold on ebay if you want an auction type setting. Otherwise, sell privately to another collector or at a shop.