I have only used a traditional course, Ultimate Italian: Beginner-Intermediate
, but I thought it put me in a decent position to read literature afterwords. All you really need is the grammatical knowledge combined with vocabulary learning. If you want to jump into reading, the best way might be to give yourself a crash course in grammar, followed by sustained reading and lots of vocabulary study/look-up. Personally, I find it useful to have a grounding in the colloquial language--even just a bit--before experimenting with the literature.
I found this book a fairly useful quick overview of the grammar: http://www.amazon.com/Essential-Italian ... 581&sr=8-8
Then you could tackle your favorite text (Dante and other old writers will require specialized help) or maybe try out a dual-language reader. I have this, and it's cheap and interesting: http://www.amazon.com/Italian-Stories-D ... d_sim_b_18