Larry-
Welcome. Not to discourage you right off the bat, but please don't expect to find sellable quantities of gold in a hurry. Unless you just happen to fall into a pocket, it just won't happen that easy. Don't expect a windfall, gold is hard to come by and every flake is earned by sweat and sometimes some blood. In most cases you will get more lasting friendships and outdoor exercise and experience than you will gold, but you will treasure all of it.
Gold is sold by weight and purity. If you don't have it smelted to a bar or button and the impurities removed you will get less for it. Gold as found can run from around 65% (from one area near me) to 95% + in purity.
Get with a chapter in your area or other prospecting / mining clubs and talk to folks on buyers they have had experience with. The cas for gold outfits pay the least and if you have nuggets or pickers, ebay can be your friend as prices are way higher for small quantities there.