If memory serves, I took it to a shop, paid them to hook it up to a emissions machine and do a quick verification that the brakes worked and stuff, then they gave me a paper showing that it had passed, as well as a sticker in the window, and I took the paper to the license bureau to get tabs.
Far worse, though, was paying "personal property" tax -- I remember thinking it was pretty sweet, the first time I got license tabs, because it was only about 20 bucks. Then I got my PPT bill at the end of the year, and it was over $300 for my car.