@tigers88 - You are right that there are a lot of these kinds of jobs. Any place that has live music or really live sound of any kind needs an audio engineer. They also work in recording studios of all kinds and are involved in any project to capture sound.
Despite the fact that they are in high demand, you will not often see these jobs listed in public classified listings. There are a few places you can look though
Post an ad online offering your services free or cheap. Be sure not to be picky about the kinds of bands your record. A good sound engineer will be able to work with any style of music.
Get involved in your local music community and be sure to meet promoters and club owners. These types are always looking for a good and reliable engineer.
Become a member of the audio engineering society. They maintain a job board and have lots of great information for job seekers. Hope this helps. Good luck!