Sure I can help out.
First of all Pond Scum is what Cardinal fans called the NY Mets in the Mid-80's. It was started by shock jock JC Corcoran, fueled by a good rivalry between two good teams. Increased, when Keith Cocaine Hernandez got shipped to the NY Mets for Neil 'the worst trade the Cardinals Ever Made" Allen.
Second-There are not any pool rooms in a neighborhood you can walk to. St Louis is not that kind of town. There are bars with bar tables, but that is it. If you stay in the Central West End or U City/Loop Area you can take the Metro Link across the river to the Casino Queen & then a cab from there to The Break in Cahokia. That would be your cheapest route. Not sure what time the Metro Link closes down. I am sure you can do a google search & find that out. During the day, you can take the Metro Link in the other direction to the Airport & then take a cab from there to Cue N Cushion billiards. Also has a website, you can google that too. That is the main daytime pool room with lots of regulars who play their regular games. There are a few younger players that would most likely match up a game with you. Craig, one of the owners of Cue N Cushion, posts on AZ regularly. Nice guy, nice family owned business. Large assortment of cues. Nicer ones you have to ask him to bring out from their hiding spots. South County is home of Sportscenter & Ride the Rail. No Metro Link to there but you can get some action if you like.
Also, not sure what your preferance is (using the word nabes has me wondering), but if you stay in the Central West End it is also known as the Central Rear End. Large gay community. Here is a free tip for you--bars that don't have a sign over the door are gay bars. They have straight bars in that area also.