I'll re-post something i posted years ago and add a fw links to shorter texts:
Italy 1977-78: Living With An Earthquake - Red Notes
Working class autonomy and the crisis : Italian Marxist texts of the theory and practice of a class movement 1964-79 - Red Notes
Italy: Autonomia: post political politics
Storming Heaven: Class Composition and Struggle in Italian Autonomist Marxism - Steve Wright (should probably be your intro text along with the essential intro.chapter to
Reading Capital Politically).
Books for Burning - Negri
Revolution Retrived - Negri - two collections of his fine 70s work.
Radical Thought in Italy: A Potential Politics. (pdf)
Other interesting/useful stuff:
Strike One to Educate One Hundred - early red Brigades stuff - up to mid-late 70s
Stefano Delle Chiaie: Portrait of a Black terrorist - fascsist terrorism in post war Italy and the links with the state, NATO, gladio etc
The Revolutionary Mystique and Terrorism in Contemporary Italy - Richard Drake (interesting but his interpretations of what marxism is/was is way off, but this has loads of stuff that others don't
The Judge and the Historian - Carlo Ginzburg, great investigation into the fallout fo the bomb PInelli fell out of a window for.
The Italian Resistance: Fascists, Guerrillas and the Allies - Tom Behan
Long Awaited Moment: The Working Class and the Italian Communist Party in Milan, 1943-1948 - Behan - both these cover the potential revolutionary moment immediately after Musso's fall etc
Moscow and the Italian Communist Party: from Togliatti to Berlinguer - Joan Barth urban
The Italian left in the 20th Century -De Grand, standard intro text.
Also, a fascinating book, Between Hollywood and Moscow: The Italian Communists and the Challenge of Mass Culture, 1943-91, goes very well with that Bona della book i mentioned above.
For short intro texts:
Our operaismo - Mario Tronti
The Renascence of Operaismo (recommended)
There and back again: mapping the pathways within autonomist Marxism
From operaismo to autonomist Marxism and
The limits of Negri's class analysis: Italian autonomist theory in the seventies both offe excellent critiical thoughts from within/sympathetic to the tradition
This is barely scratching the surface to be honest.