There was a stray running loose in my neighborhood quite a while back. I lured it with a can of tuna. It was looking for a home so first I called the number on his collar and a guy came and picked him up. The cat escaped from his car before they left the condo grounds and when I came back from working out I got the full story from a neighbor, guy was a real jerk. About an hour later I found the cat again. This time I tossed the collar, took him to a vet for a check-up and shots, and over the next few weeks/months proceeded to get him back up to a normal weight. Great cat, very easy going, had him another eight years.
In your case, I'd get one of the live traps available through animal control and let them deal with the problem.