Hello, I'm actually going to Platt College right now in the Baking/Pastry program.
Given I'm going to Platt, I have a unique perspective as to how much it costs. I also have dug around before starting school here, so I at least have a tiny bit of perspective at some of the options for school around this area.
Unfortunately, Platt college is probably one of the cheaper colleges you can attend to actually get an associate's degree in Culinary Arts, at least for a dedicated Culinary School. In fact, I'm pretty sure Platt is the only dedicated culinary program in Oklahoma. I may be mistaken, but I'm pretty sure your only cheaper option would be going to a traditional college (via a Hospitality Services program) or a community college. Traditional colleges can often cost just as much as a Culinary School, so if price is the main issue, you'll probably be better off digging around some community college or tech school programs.
These programs aren't necessarily bad, just amazingly cheaper. The school may not be accredited, so take that into mind if it's important to you. Something you may want to look into before looking outside the state (and this is assuming that your in the Oklahoma City area), you could look into Francis Tuttle's culinary program, or even the 105 Degrees Academy, if you're into that sort of thing (it's a raw food dedicated culinary school located in Oklahoma City).
I'm sorry I can't be of more help, but a lot of the schools that I know off the top of my head are going to be more expensive than Platt. Like there's a Cordon Bleu in Dallas and a Johnson and Wales in Denver. Both are good schools, but both will be expensive. There's also some of the regional universities in Oklahoma that have culinary programs. You could look into those as well.