By "they", do you mean your college? They should be able to tell you what accommodations they can provide for students with ADHD, because a lot of students have this, so they must have it all worked out. If they can give you a list of accommodations that are available, it seems like you could choose which ones would help you? What did you mean that everything is an hr or more away?

That's too bad the clinic you went to can't prescribe Ritalin. Why don't you take documentation of your ADHD diagnosis and go to a full service clinic that can prescribe whatever medication you need? Also take information on the meds you were prescribed that didn't help.

Good luck.