That would depend on the question.. For Basic questions, Basic Drug Discussion of course.. But for something more than "basic" I'd suggest Other Drugs
btw, Welcome to Bluelight
Please read the Posting Guidelines for each forum and don't forget to use the search engine. Cause chances are someone may of asked the same or similar question you have.
^Yep, good answer. Please read before you post. This is entirely the wrong area for a question like this and with just a little looking around you could have easily found it on your own.