I use this book more than probably all my other reference materials put together. This book provides information across most UNIX platforms ie Linux,AIX, Solaris, HPUX etc. This is a must have for Sys Admins of all levels.
Samba is fairly simple at its basic configuration. When things start getting large and complex is when this book really shines. The authors give examples and scenarios of small simple configs and works their way up to very complex configs. Consider who the authors are and you can only expect the best.