Hello, where can I read about some basic properties of twisted D-Modules? I would like to know, a reference, that describes how to glue these modules together/pull them back/push them forward.
You would probably do well with any of the resources under "D-modules" on Gaitsgory's page. Ginzburg's lectures are good, as is the book by Hotta, Takeuchi and Tanisaki.
Others have posted links to a scan of the Beilinson-Bernstein paper on Dennis Gaitsgory's page. You can find a different scan on Joseph Bernstein's page, where it is number 49.