I've used California Numismatic Investments. Found them to be totally reliable with good prices. Here is the website:
www.golddealer.com. They also sell silver, platinum, and paladium ( not spelled correctly).

If you are interested in investing in gold without taking possession, you might also look at these sites:

www.everbank.com ( They sell a gold CD and a silver CD)

There is also a gold exchange traded fund you can purchase if you have a stock brokerage account. It is offered by Ishares, and the ticker is GLD. The silver exchange traded fund ticker is SLV. So, there are a lot of ways to invest in the metals, without trading futures contracts!