Hello "The Forgotten?" , GTA4's nightclub can't be opened, so I think you're asking about the music for the Sassy Tony's Song (GTA4's DLC) nightclub. It's not very easy to find online so I'll just send it to you. (The song in it is played on a loop in the nightclubs, three nightclubs in a ****, and the music is different in each one. The music sent here is from Bahama Mamas, the beautiful nightclub that you can only enter once in the quest, if it's not you can find me again)