I use the Blackstone all-metal (well, almost all-metal) pump. Looks almost exactly like the pic Al posted, except the pumping cylinder looks a little longer. Same effect though. Using these is very, very easy in most cars. Get the oil hot, shut off, pull the stick, insert the tube, pump, and that's it. If you're working fast and carefully, you could do the whole thing in sixty seconds. I usually suck out a couple bottles full and discard them just to make sure that the end of the tube didn't catch any crud on the way down (thus theoretically dirtying the first sample).
Very easy, very recommended.