The administrator's manual and most of the documentation are available in English only (no French version). Many French-speaking people are surprised at this because the authors are French but it is really difficult to maintain a documentation even in a single language.
Versions prior to 5.3 included latex documentation. We now moved to a wiki because we want to encourage contributions to the documentation, which will be far easier with a wiki.
Administrator's manual: this is the main documentation for installation, setup and customization of a Sympa mailing list server.
There are many sources of documentation about Sympa.
For users, the main are included into Sympa web interface (since version 5.2.4 and later).
We've listed Sympa user's documentations of interest.