If you are inclined to buy only one coin, go to your local coin or gold dealer and buy it there. If hell bent on shopping ebay, have knowledge of what and how to buy it there.
If you are really serious about swapping your fiat money by buying substantial amounts of gold and building a gold stash, read below. I posted this a while back for another guy wanting to buy gold:
Try coloradogold.com. Read the article, "Looking for Rare Coin" on the front page, the article with the BIG RED X on it. Buying collectible coins is not worth the costs. Buy bullion coins, bars and rounds, keeping in mind that you are looking for the most gold in OUNCES at the cheapest price possible. Buying bullion, in place of graded coins is the best way to ensure quick turnaround of your gold when time to sell because that type gold and silver is most popular. Numismatics (collectibles) only limit your market when trying to sell quickly, plus they are a rip off with extra premium you must pay for them.
I also suggest getting some 90% junk silver, which usually comes in $1000 face value bag (1 or 2 bags minimum). One ounce gold Swiss bars, usually certified with a serial number for authenticity, are good value. When buying bars, buy those with a benchmark stamped on them. NEVER buy bars without a benchmark (the company that made the ingot). You never know the purity or authenticity of a bar without a benchmark. Also, consider small gold coins 1/4 and 1/2 ounce, that you can carry with you if you travel to another country (or here). ALL countries will take gold and silver coins, above and beyond fiat money. The smaller coins allow you to sell a small amount of your gold in place of the larger 1 oz coins. Why have a pocket full of fiat when you don't need it?
Finally, think about silver. Historically, the ratio of silver to gold has been around 15:1. Gold is now $1167. Silver should be somewhere around $78/oz, but is now $18. Not a bad investment, right? Even if it doesn't reach the historical ratio, silver is going to go higher.
Get yourself a good safe (or hiding place) and insure it with Smith and Wesson. Most of all, keep your mouth shut about what you have. Good luck and hope this helps you protect what you have worked so hard to save.
If you are buying gold as either insurance or an investment don't get too wrapped up in which coins. That's for rare coin collectors. Eagles and Buffalos both work well. Stay away from Ebay and similar venues. Buy only from reputable dealers like Kitco Monex bulliondirect etc.