Well Haze Nightclub is inside Aria.  

Eve Nightclub is right next door inside Crystals.

I have been to both and they are decent.  Plenty of other nighclubs all over Vegas.

Taking my ATF to Vegas with me and we like to party at NYC night clubs. Staying at Aria in City Center, She is in her mid 20's and I'm in my mid 30's. I'm all set with some providers for some 3 sums, but i wanted to know where some regular action might be?

XS at the Wynn Encore is great.  Pure at Caesars is fun, plus it has a lounge with a Las vegas version of the Pussycat Dolls, which is worth some time.  Both of these have seating outside as well- it can be nice to get out of the hot, crowded DanceFloor.  Marquee is the hottest club right now, I think- opened New Years at the Cosmopolitan.  I have not been there- next on the list.  Tables seem to be about twice what they are at the other clubs.  Playboy club/Moon is good as well.  Rain is a very young club with lots of people rolling (in my experience) and I would avoid Jet, which I have been to.  Most of these clubs get very crowded- if you can afford table reservations, that is the way to go.  Otherwise expect large, long, unorganized  lines

Without a doubt.

http://jackcolton.com/

He also has a lot of tips on how the scene works (including direct contact with club VIP hosts, so you're not dealing with two sets of hosts you're toking).

what about us guys that are 50- any good place

Aria's Club has plenty of us mature folk when I was there

Besides, age just a number bb, go ANYWHERE you want and have fun

I am 50 and I have been comfortable at every club I have gone to - I think age is somewhat irrelevant in Vegas.

I highly recommend XS as well Tryst at the Encore/Wynn, Vanity is good as well, Moon at the Palms has a great view.If you want Lounge type Ghost Bar is best and for after hours of course Drais.