There's a place on 24th between Castro and Diamond. I inadvertently got a buzz cut from these folks back when they were located on Church. I can't say that it was a good buzz cut or a bad buzz cut-- just that I didn't want a buzz cut and got one!

You might just try playing grown up, plunk down your $50, and get someone in a salon to do it for you. Might not be your deal, but it could be worth a shot. Joel at Isa's (Castro at Jersey) cuts the hair of most people that I know in SF. He uses the clippers now and again, so a buzz probably wouldn't be a huge stretch.