i know this must be another stupid question, but are there any shops that sell uk garage or any garage clubs in poland?
You should look it up in some vinyl shops or via Internet. There are no clubs exclusively playing garage but there are parties with house, garage, etc music.
I think near you in Gdansk or Sopot there are certainly parties with such music just google a lil bit.
detestudio.nazwa.pl/BLOG/?tag=uk-garage