(especially people who might speak english)
That's not who you want to be targeting, Poland in English is not nearly as interesting as Poland in Polish.
I second the dancing classes. Look for people who practice other hobbies you might be interested in. Chances are there are people who are also interested in it in Poland and getting to know them will help your integration and language skills.
Where do you live? Lots of neighborhoods have bulletin boards for community center events.