E-mail coaches in the area and ask if they'd like any volunteer help a few times a week. It's a great way to get your foot in the door, and if a paid position opens up, you're more likely to get the job since the kids already know you. It's also a good way to get references and experience on your resume.
When coaching positions open up in schools, school employees are often aware (and they tell other people) long before the job is posted in a newspaper. Volunteering is also good for getting "in the loop" for these kinds of openings that are sent through the grapevine.
For all-star coaching positions, they are usually advertised publicly sooner, so newspapers and online job searches are probably as good as anything.

im starting my own cheer squad and maybe you can help getit off the ground cause i need a couch if ur interested if not its ok

I was in your position for a long time. I emailed tons of coaches and they all failed until I finally found a req team to work with and I love it! It's a great way to get experience. Just look online and email email EMAIL.

no im in southern california sorry bu i hav cousins out here that migh wanna help