I have found that cradle Catholics from polarized environments tend to have the most vocally negative attitude towards Protestants.
Converts tend to be the most conciliatory towards Protestants due to experience. Bob the Baptist is the same guy now as when I was Benedict the Baptist.
Based on that, you will want to join a congregation that is perhaps younger and includes a number of converts rather than an older congregation in an historically Catholic neighborhood. If you live near a Paulist parish[/url:2yd2d7s1], I can all but guarantee they will be friendly and accepting (you just have to watch out for orthodoxy as some Paulists are a bit out there; St. Paul the Apostle church in New York City used to be my parish).
If there is ever any hostility or condescension towards you personally or Protestants in general in your parish, speak with the pastor and, if it comes to it, move to a new parish.