I was on a field research team in California's grasslands several years ago, and ticks/lyme disease was always on our minds. We usually caught the nasty little bastards before they dug in though.
However, if they did manage to latch on, the best way to get them out AND minimize the chance of catching lyme disease was to dig into the point of contact with a set of small tweezer, and pull out the buggers by gripping onto the head and pull with a slight twisting motion. Make sure not to crush the head or else you chanced infection.
Some people coax ticks out by using strong smelling chemicals like alcohol or tiger balm. Some even try to burn them off with cigarettes. However, the problem with the chemicals is that sometimes it causes the tick to literally vomit into the wound, possibly spreading lyme disease.
It's been a while, but if I remember correctly, lyme disease is a much bigger problem east of the Rockies. One of the theories why California had a relatively low number of cases was because of an intermediary host animal for the ticks. One type of California fence lizard favored by ticks had blood apparently very hostile for lyme disease and thus by the time the ticks jumped from lizard to human, the lyme disease bug was incapacitated.