This guide has covered a wide variety of important threads programming issues. Extended Example: A Thread Pool Implementation provides a pthreads program example that uses many of the features and styles that have been discussed.
For more in-depth information about multithreading, see Programming with Threads by Steve Kleiman, Devang Shah, and Bart Smaalders (Prentice-Hall, published in 1995). The conceptual information is still valid.