hello
First off the czech girls are not so impressed with foreigners as they were 10 years ago.
Now clubbing is just like anywhere else in the Western world.
When you come to your hotel check out the section with flyers and adverts.
Also ask the barman or bellboy what they would recommend.
I know a couple of places
www.musicbar.cz is full of locals
Also there is club11. The night I was there I am pretty sure I was the only foreigner, but I was drunk and cant remember much about the location of the place. It was somewhere between the wenzelssquare and the carls brigde. So good luck finding that one
The 3 largest discoes in Prague are
www.lavka.cz
www.karlovylazne.cz
These 2 are right next to the carlsbrigde and full of mostly tourists but there are also lots of locals.
Then there is
www.duplexduplex.cz
This is an upscale club, difficult to get in on weekends and they have a "casual smart" dresscode.
Other than those places mentioned here, Prague is full of bars and clubs.
They all have cheap entrance fees and have cheap beer.
Here is a link to a clubguide
www.badpoint.com/art.asp?id=110
Last a word of warning.
On the wenzelSquare (vaslavksa namesti in Czech) there are people offering to take you to stripclubs, discoteques and casinoes.
Almost all the places they will send you to, are tourists traps so awoid them like the plague.