Actually, it was not spot-on. She said the university is not responsible and that OP has to find his own note taker. There's plenty of case law that says otherwise.
Can't argue with that!
While they need to provide something, a "note-taker" isn't necessary the accommodation that can be provided (in fact, the statute and guidance doesn't even talk about note-takers." If a reasonable accommodation is a tape recorder, then that's all they need to provide. They don't need to just provide anything a student alleges they need for their accommodation.
Getting back to the original question. You are going to have any lawsuit dismissed before it is even heard if you don't avail yourself of the proper procedures.
The first is to contact the ADA/504 coordinator which all schools are obliged to have (and was already suggested earlier in this thread). If the coordinator can't either arrange the accommodation or correct the misconception the professor is operating under, then you can file an grievance with them to escalate.
Then, you have two options (you may indeed do both). You can file a complaint with the US Dept. of Ed's civil rights office. The other is that you can file a federal lawsuit asking for injunctive relief (it's unlikely you're going to get money out of this. You have not hit the lawsuit lottery ticket here). Damages are only award in the case of substantial and intentional discrimination.