Drachen's link is pretty good, so I won't go through the process. Time line from arrest to trial varies by jurisdiction. It also varies depending upon whether the accused is in jail or not. Normally you'd expect the trial at somewhere between four months to eight months. Shorter is not likely, but longer definitely is.
Complexity could result in longer time period. Delays due to attorneys' schedules, length the trial will take, courtroom schedule all factor into this. From the point of view of the defense counsel, if your guy is on the street, the longer this takes, the better. I've seen criminal cases that take three or four years to get to trial, and they sometimes take even longer.
One thing TV and movies don't represent accurately is the time lapse for labs. If you're looking for DNA evidence, it can take several months, depending upon the workload in the lab and the priority of the case. I had a client who served his sentence for stealing a car (somewhere around six months if I remember right) and been released before the police got his fingerprint identified on the car's mirror. (They didn't need it as they had a crapload of other evidence, enough so my client had no doubt about accepting the plea offer.)
Best of luck,
Jim Clark-Dawe
