Waiting days for a doctor's appointment can make you extremely uneasy -- not only do you not know what that lump is, but, more importantly, how are you ever going to find out what sort of crazy situation Goofus & Gallant have gotten themselves into now? Giving you near-immediate answers to the first of those questions: ZocDoc.
Just launched in LA, ZocDoc is exactly like OpenTable for MDs, w/ over 100,000 appointments available right away, which means you can get checked out far more quickly than the alleged average of 24 days -- although, four more, and you'd get to meet a sauced up Sandra Bullock, plusss the dude from The Wire who played McNulty and Aragorn! Using it's simple: first, input your insurance provider, then ZD'll spit back a list of docs with available times (possibly as soon as that very day), brief bios, and user reviews, because, who better to turn to for advice on a doctor than "MoneyRashHoes69"? Guys/girls with stethoscopes and white coats are also searchable by specialty and're updated in real time, and once you pick the doc you want, all you need to do is let them know why you'll be visiting, or to save time, just say "symptoms comparable to user name MoneyRashHoes69".
Of course, they've also got an iPhone app, which also allows you to book outside of LA -- so if something happens in Tucson, you can always Ask (for) Arizona.