This article is from the Go FAQ, by Morten PAHLE firstname.lastname@example.org with numerous contributions by others.
Probably, yes. Go has been blessed with a large number of contributors
providing tools for every conceivable function.
Programs related to Go perform several functions:
Play Go (i.e. be an opponent)
Clients to the Go servers
See section 3.3 above
Read/edit Go files
Teach games and sequences
Create and solve problems
Create Go diagrams
Translate one Go file format to another
Some programs perform more than one of the above functions.
The list of programs available is too long to be shown here, but the
links above should be able to provide the answers required.