I can tell you of two of the biggest pool halls in Bucharest.
Fisrt one is the biggest one in Europe i think , has 43 GCIV tables and it's called IDM www.idmclub.ro site is only in romanian but you can tell any taxi driver they will know . Couple of players there but most of them are in ..
King's Club www.kingsclub.ro also it's only in romanian language. This is the pool hall that most of the good players hang out in . The tables are the official tables that are used in the Eurotour .