it probably depends on the church. the church I attend is pretty laid back with their dress code for one of the services, so they would be perfectly acceptable for that time. however, some members, (often older, more traditional members) might frown upon your casual dress. I would say compare what you hope to wear to what others are wearing. I also think that it really should not matter though, because church is the place where all people are to be accepted, so wear whatever you want, because I don't think god really cares
A good church won't care what you look like because Jesus just wants to love you and get to know you. He doesn't care how your dressed or the tatoos that you have he just cares about you and is happy that you are there.
It depends on the church, really. Some are very casual, while you might be better off dressing up just a little for others. It also probably depends on when you're there. Sunday mornings might be different from Wednesday nights. Maybe you drive by and see what people are wearing when they come out, or just wear something else for the first time until you get a feel for it.