need quick alignment help

I am taking in my '05 Prius tomorrow morning for some things that are not working right and I can't find where the specs are that are best for an alignment. I mentioned that I thought there was a free alignment under 12,000 or 12 months [Nov. 5th]. They didn't seem to know about that and I don't know where it mentions it. I told them to check it if there was.
What should the numbers be that are best for my front? back? tires so I can have them printed out when I go in.
Any reason why I shouldn't have the alignment checked and possibly redone. Sometimes it's better not to fix something that is't broken.
Any help will be appreciated and I will keep checking back here before I go.

Thank you.