As Dave mentioned, you should have received stickers when you paid. Otherwise go to AAA, they will take care of you. Unless you are just talking about the AAA stickers people put on their cars. There's no need to do that. Don't do that. There is no benefit, it messes with your paint, and people assume you are covering up a ding.
Yes, go into the office and they will handle everything. Should call first to check and make sure they will handle it at the front desk.
Did your registration come in the mail? If not, I would suggest calling the DMV if your check cleared.
If you mean for car registration, you receive them on the spot when you renew. Not sure what others you might be asking about.
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