Some great Hotspots for what you are looking for:

Eleven50, awesome club, with VIP area, amamzing dj's all around wonderful vibe in Midtown.

Cosmo/Lava: Also in Midtown, this club is actually two houses combined to make for an amazing nightlife experience!

Tongue and Groove in Buckhead just had a facelift and is beautiful! Great mix of people, two dancefloors. Very sexy.

Compound, this is such a cool club. Indoor, outdoor venue, gardens, ATL hotties everywhere!

The Mark: This venue has more of an underground vibe. Top deejays from all over the world come here. Great VIP area....

Wild Bill's: This venue is just North of Atlanta. It is the biggest Dance Club in the South. It can hold 4000-5000 people. It has everything including a mech. bull.

Hope this helps!

Matt