I got into it by chance as well, my friend owns a surveillance company. I don't come from a networking or tech field, but I quickly learned...
I would say, if you know how to run wire or are serious about it, learn what it takes to run the wire. Then learn how to use the necessary adapters. Most companies build their own DVR's or are PCDVR's. So if you know how to do some of that technical aspect you should be set. Some companies do hire, but the best thing to do is like most say, go on the internet, and see what places are hiring.
What city are you in?