There is some good places in St P to play different kinds of billiard. I liked this place when I was there for a visit.
And if you ever have the opportunity, try russian billiards. Then we start talk about tight pocket Gave me a real kick and made me start play again.
if you happen to be in St Petersburg you'd better try Leader billiard hall (you could of course visit Leon TOO): liderclub.ru . It is not open 24 hours, closes at 6 am, but it has another advantage, as a place of interest as well, it is the biggest hall in Europe.