The best place in the city by far is Opera. It's in the middle of Midtown, right in between Midtown and Arts Center MARTA stations (that way you only pay for the cab home!) on Crescent Avenue. It's also right near tons of restaurants so you can start early and head over to the club.
Good crowd, no riff raff, they keep it exclusive like they say they do. Wear your finest attire and bring your A game. Three different types of music- Mainstream/Hip Hop/Top 40 in the Main Hall, Latin/Salsa/Meringue in the back room and then they do House on the Patio. That way you can take a breather, spread out and see some different sights and sounds if you need the break.
They have bottle service if you choose, and I ALWAYS say that it's the best choice for you if you have a group of four or more-- no waiting in line to get in or for drinks, you can pour it as strong as you want and you have a place to sit and chill out.
They have a website, Google it and have fun. Peace.