From what I have found online and in the samba package, there is no good
documentation for libsmbclient. This is an extremely useful library that will
have lots of applications, but it is very hard to figure out the API only by
looking at several small example programs.
The header file is quite well documented, you might want to give that a look.
Haven't heard back about this report. More documentation for the client
libraries will be included in Samba4.