you can try to join one of the groups at meetup.***
Some of them cost money (I've seen offers of up to 12 € per session), but a lot are for free.
Another oportunity is to go to the HTW (University of Applied Sciences). There you can use the library and the "Mediathek" to learn a language.
Here's the link to the mediathek:
There you can find open hours (Öffnungszeiten) and the address.
It's only in german, which I hope they improve soon.
I hope this helps.