My wife was a police office for 16 years. The majority of large cities don't require any college degree- you have to pass a civil service test and then get picked during a "lottery" of the top scorers. Military and education do score you points during the process however.
Salary can vary depending on your area. We were lucky enough to be in an area where police are paid extremely well. Some areas don't make very much at all. Check the pay scale before starting.
Personality-wise, if you're not a naturally observant and confrontational person, this may not be the job for you. Those two factors are key to the job. Backing down or missing a detail can be very dangerous.
Over all, it's not a career I'd recommend if you're planning on a family. It tends to make you a jaded person because all you deal with are problems. Over the years you end up not being to turn off the suspicion and it becomes difficult to maintain a relationship (infidelity and divorce is incredibly high among officers).
Most departments have a "ride-along" program where you can schedule to ride with officers for a shift to see what they do. I'd suggest trying that to see if the job is for you. My wife was seriously injured and forced to retire from the force, so it has significant risks, but she says she would do it again in a heartbeat.
