Lam wasn't available? Now THAT's weird. His books should still be lying around in every "kiosk". Well, maybe that's a tiny exaggeration, but a huge collection was released and sold via "kioski" and I remember seeing leftovers quite recently in a normal kiosk in the centre of Warsaw.
If I were to risk suggesting another translated author it would be Ryszard Kapuściński. Masterful documentaries form around the world, but the language is quite rich (not to say ornate), so he might prove rather difficult. And if s-f is your genre of choice there is Janusz Zajdel (a few of his books seem to have been translated) - quite known in Poland, though his books had a sharp political edge (against Communism obviously) so for a foreigner I guess they could have historical/curiosity shop value mostly.
> Blogs tend to be short and snappy and dialogue rich.
Just ask someone to check if they are also grammatically and stylistically more or less correct. :-)
BTW - for listening comprehension: http://www.polskieradio.pl/podcasting/show/?nr=10&name=trojka