1980-89 is pretty weak on their reading list, which would provide some insight to your question of how to overthrow a police state without external forces. Reading Timothy Garton Ash's work on Poland (The Polish Revolution is a good starting point) gives a lot of perspective into how a conservative Catholic majority can be the impetus for revolutionary change, and with greater earnestness than the dissident intelligensia at many times.

For theory, Havel's work is a bit out there but definitely interesting. Try "Power of the Powerless" and "On Evasive Thinking" (it's in his Open Letters, I think); these are two of his best political theory essays. Havel's a bit of a contested figure, but I think it's fair to say that he roughly lives by the principles he expounded in his theoretical works, and that his emphasis on public dissent as a means of taking down authoritarian regimes heavily influenced other East Bloc dissidents.