I never birded there myself, but heard that very good are sea pier at Swinoujscie and industrial pools near Police power plant. I suggest contact website clanga.com. They are very good Polish twitchers based at Szczecin.
Thank you Jurek. I've emailed them but haven'y had a response as yet. It does seem that British bird watchers all go to Eastern Poland if they go to Poland. Strangely, I had the same problems getting information about Rugen in Germany. Of course, I might just be looking in the wrong place.
I come from around. You probably don't want to miss out on the Nature Reserve Świdwie. I am a beginner in birding and don't live there anymore so I cannot say much about it. Definitely want to visit the place once I can afford a scope. But one thing I can say for sure - when you are from around you don't have to be a birder to know that this place is pretty famous for its birds diversity. There is a chance to see white-tailed eagles.
Have fun, and in case you decide to go there, please put few words here, how was it.