There may be ½0 oz bullion coins. They contain that much gold. At that small amount, you may be paying more like $55, or a 10% premium because of the small quantity. China may mint bullion coins in that small a size. All of my gold is in 1 oz coins, purchased by the roll. Short of buying gold bars, that is the most cost effiecient way to buy. Current quote (2FEB10) is $23,695 per roll of 20 US Eagle 1 oz coins. These are fresh from the mint. A coin dealer can probably beat this slightly on circulated-quality coins, but the vast majority of valuation is based on bullion content, as these are not collector items, but a recognizable inflation hedge.
Buying small quatities of gold is only worthwhile as a long-term hedge. Bullion would have to rise at least 10% for you to break even when buying the 1/10 oz or smaller coins.
Given the record US budget deficit buying bullion gold any way you can is probably a good idea. I doubt if gold will go lower than $1000 per ounce any time soon.
Another hedge would be to convert your dollars to Euros, Sterling or Swiss Francs.