for advertising, phone book, of course.. if you want children, i'd also consider talking to some schools in collinsville.. maybe you could arrange it so you could do a presentation of your artwork for the school's kids (either an assembly type thing, or in the art class itself) & giving the kids some fliers to take home to their parents about your services.. you could also do newspaper advertising, it's more expensive, but if you could do an advertisement in a sunday paper, when most people buy papers, then you could get some folks that way. also local papers. you could also ask if you can leave fliers at day care places, local coffee shops & etc.
i don't know how young of children you're wanting to teach. lol if you want the really young ones, day cares would be good.. if you want middle school/highschool kids, i'd see if collinsville had an alternative school, because alternative school kids aren't always ones with behavioral problems.. they're extremely talented & if you could reach them through art & help make them better people or whatnot.. that'd be great.
another option would be, since you're an artist.. designing your own brochures, instead of or in addition to a flyer. you can download some free brochure templates for microsoft word online & just add a background you've designed (you can scan a piece of art & use it in the background, doesn't have to be digital).. you can also make your own bullets or whatever & give some samples of your artwork, maybe pictures of you teaching children or whatever you have available to you.. include info about what you want to teach, your objectives, what kinda stuff the children will learn, how it benefits the children, etc.. then you can either print them off yourself (ink is expensive, though), or have kinkos do it (which is really cheap). you can email kinkos the finished product, put it on a disc, etc.. if you have photoshop, you can create the brochures in that, too!
another good thing you could do, would be to design your own business cards. either scan your own artwork & use it as a backdrop in photoshop, or use photoshop/illustrator/etc & create it.

if you have an interesting business card, people will be more likely to remember it/keep it. it's also not that expensive. vistaprint.com has inexpensive printing costs. i have designed all my own business cards & it's not that expensive.
hope that helped!!
