Another idea: Sell products and services on your site that have a higher mark-up (say 30% to 100%). This could possibly give you enough profits to make the "thin margin" sales (Amazon) worth the trouble and risk.

I've been thinking about these things myself because I am in the same "thin margin" situation with GoldStarBullion.com. Fortunately, I am a net accumulator of BTC and I have been able to weather the dips in BTC's exchange value. That said, I can appreciate the need to minimize exchange rate risk as much as possible.