What about trying to buy Bitcoins from a country that isn't the US? I shouldn't have to send you the left arm of my first-borne to verify I'm a human being and then be limited to performing any transaction in dollars.
If you ask for non-US based services, it's probably worth specifying where you are. BTC exchange services are very jurisdiction-specific at the moment.
Edit: Well, currently they seem 50% overpriced, so maybe this is not such a good idea, unless you really just want "some" BTC to use instead as an investment.
If you have USD in cash, you can sell them for close to 10 ARS and then buy BTC at about 7.34 exchange rate.