Why not go and take evening classes? I once took some at a institute here (where I live) called 'The British Institute' and in my opinion it's much more effective to go and have proper lessons. That said, I've noticed that some tutors regularly post in the Comments' section, so that could be an alternative, but using classical books will probably be the most effective way for you to get going. (I noticed you made some slight mistakes and concluded you might have a bit to work on, with all the grammar, vocabulary and so on.) In any case I couldn't be 'a tandem partner' for English as it's not my mother tongue, I only have what I was taught in school + those lessons from a Welshman working at the said institute. (That's how I came to learn that the leek is Wales' national symbol.)