Some club links.
Samara Night is the "what's on" of Samara, which has club reviews, addresses, and upcoming concerts at all the clubs.
Metelits-C - This and Poljot are the biggest clubs in the city. Metelitsa is higher-end, but still a mid-range club (Poljot is the lowest end and dangerous). Several dance floors, many bars, can hold a few thousand people I would think. The two dance floors on the first floor are R&B and the best place to game.
Poljot Club - Big club and aerosopace-themed, so kind of fun. Cosmonauts and heroes of the Soviet Union get in free. Several dance floors on two-floors. Downstairs is 80s music, upstairs techno and R&B.
Rock Bar "Skvoznyak" - The best place for ONS in the city IMHO. Lots of slutty women from mid-20's to mid-30's. You won't find the 18 year old stunners here, but still very good babes who are into American/Western culture.
Rock Bar "Podval" - The other rock bar. This one is not a club like Skvoznyak, just a grungy basement bar. Surprisingly good food and cheap beer prices. Nightly concerts in a small environment. Good for making friends and pregaming. People tend to be nice to Americans/Europeans and interested in practicing English (no thugs like in other clubs).
Night Club "Lust" - Upscale club, lots of stunners here when I was last there in 2010. Features things like nude gogo dancers in body paint, ice shots, etc.
There is also "MTL-Arena" which is a club that holds big concerts from time to time. I didn't go there.
If I were you and you are there during June or later, then start out in the evening on the embankment and see what's going on. Check out the entertainment centers right off the embankment too (you'll see them). From there you could walk to Skvoznyak or Long Bar or Zvezda since they're all together in the same complex. They're a 10-minute walk after the very northernmost part of the embankment.
If the embankment is not yet really open or with people (it should be by mid-May or so) then try Podval for an early-evening concert.
If those all suck then take a taxi to Lust or Metelica-C. Like I said Metelica-C was my favorite club, I had many fun nights there, but it's not close to any other thing, so it means taxi there and taxi back for sure (unless you stay until public transportation picks up).
Remember parties start going at midnight at the clubs usually. Get there at 11pm or so and you can have an hour to talk up people arriving early before dancing starts. Entrance will probably be 300-500 rubles for a guy, $10-$15 USD.