For me, it depends on why you want to play, or why you feel playing is necessary. For example, a poster in another thread mentioned that he was glad that he played bass at his church because he would be too easily distracted by all of the goings on at church.
Do you feel playing is necessary for you because you feel like it's one of the ways God has gifted you to be a contributor to the body of Christ, or because you worship through your instrument? Are there other reasons you want or feel it's necessary for you to play? If I were you, I'd definitely evaluate your motives before making that one of your decision-making factors for joining a church.
Additionally, as Dave may have mentioned, you certainly want to evaluate other aspects of the ministry- first and foremost, whether or not it's a bible teaching, bible-believing church. Get to know their doctrine and statement(s) of faith. Ideally, you'd like to find a church that you'd be happy to join whether or not you had the opportunity to play, for reasons like: you could see yourself growing and being equipped for ministry, etc. Then, if you're afforded the opportunity to play, it'll be icing on the cake. Be blessed.