If you are looking for coins with definite investment potential, gold coins are an excellent place to start. Though they are expensive when starting out, the investment value of gold itself makes them a very attractive option. And, because gold is bought and sold routinely on the commodities market, it is easy to stay on top of the price of gold, making it easy to follow the price of your gold coins. Which makes gold coins the equivalent of stocks or bonds for the coin collector.
Admittedly, it is not always easy to get into the market for gold coins. After all, gold is expensive, so coins made from gold are going to be pretty pricey. However, there are usually several weights available, so you will be able to find something that will fit your price range. However, when looking for gold coins, it is usually fairly easy to find a dealer. Many coin dealers are attached to the gold coin market and, if they cannot sell them to you directly, they will be able to connect you with someone who can.
There are also several internet merchants who offer gold coins, but it is a good idea to be careful when shopping online. After all, there are a lot of proper merchants out...