This is just FOIA. You don't need any special website or process; just Google [(your state) FOIA] or [(your municipality) FOIA officer]. In Illinois, you can simply email free-form requests for documents and start a 10-day clock on the public body's side.
The problem is following up. It's hard to understand the process, and what to do when the public body doesn't respond.
If nothing else, the Sunshine Request site is a good place to get form emails for these requests from.