There is a two volume book called "God's Playground: the History of Poland" by Norman Davies. For my money is it the most thorough literature on the subject. It begins in the 900s and, if you get the updated version, goes all the way to the 2000s. Very informative. It's a tad dry, however, and a more colorful yet utltimately more incomplete history is "The Polish Way," by Adam Zamoyski. Also for a contempary history around the Solidarity movement there is "The Poles" by Stevens. All three are excellent.
I can also suggest this book to you. Norman Davies is nowadays one of the best historians, he is very open-minded and detached even he's british. I suggest all his books on every topic he wrote about.
I can also suggest Oscar Halecki's works, for example: A History of Poland with additional material by A. Polonski
Cambridge History of Poland could be a good start too.
The Davies book is certainly authoritative. One that I like very much is A Traveller's History of Poland by John Radzilowski. This is very readable and "user friendly."
I will second Davies' God's Playground as it is a very good source, robust and not minor / one-line sentences about Polish history (e.g., Pogonowski's Poland). Zamoyski's The Polish Way is slightly better than Pogonowski's works. I also have found there are many amateur historians, with an interest in Polish History who compose light pieces of topical interest; capturing or regurgitating other's scholarly work.
If you are interested in a specific area of Polish History, there are many great books written at a scholarly level, geared towards academia. Search academic-driven press sources like Yale, CEU Press, Columbia, etc.
I have built my collection of texts up from ebay, and I've been very successful in building a broad-ranged library.
If you want a good reference work for Poland WWII then I would recommend Poland in the Second World War by Dr. Józef Garliński. It may be out of print but I believe a new expanded edition is being worked on by his son Jarek Garliński.
Dr. Garliński has written a number of authoritative works on Poland's contribution to the allied victory in WWII. The best in my opinion was Poland the SOE and the Allies which recounts in part the formation and military operations of the cichociemni (or the Unseen and Silent) special force paratroops of the Polish Underground Army.
Looking for an English language book that focuses on Poland AFTER 1989. Most general surveys only mention the period 1989- I am looking for a little more on things such as privatization, Walesa and future administrations, the 1995 crisis, EU membership, post-89 cultural changes- etc.
There is no Polish history after 1989. Actually, there isn't even a history after 1945. Everything happened before WW2 and then ... nothing ... ;)
This seems to be a good starter with lots of resources mentioned: euij-tc.org/pub/research_papers/20060916_TUFS_International_Symposium/The_Polish_Historiography_on_Contemporary_History_after_1989.pdf