Hi all, and thanks for the comments. My flight originates on United, and United cargo says they don't work with individuals but that I would instead have to contract with a private company to send anything via their cargo. So, even if Qatar Airways might accept my cargo, United, it seems, will not. Sooo, I have talked to United about just bringing a heck of a lot of extra luggage on and paying extra luggage fees. I find that for the (small) amount of stuff I am bringing to Doha, paying extra luggage fees is cheaper than sending with any company I've spoken to (North American, ShipSmart, FedEx). So, thought it'll be a pain in the bum to get through the airport when I arrive, I think I will just bring a lot of extra luggage, and save some money this way.

Thanks everyone! Looking forward to Doha!