You can learn more about client/server computing from the following books:
Ligon, Thomas. Client/Server Communications Services: A Guide for the Applications Developer. New York: McGraw-Hill, 1997.
Lowe, Doug, and David Helda. Client/Server Computing for Dummies. 3rd ed. Foster City, CA: IDG Books Worldwide, 1999.
Lowe, Doug. Networking for Dummies. 7th ed. New York, NY: John Wiley & Sons, 2004.
Orfali, Robert, Dan Harkey, and Jeri Edwards. Client/Server Survival Guide. 3rd ed. New York: John Wiley & Sons, 1999.
Vaughn, Larry. Client/Server System Design and Implementation. New York: McGraw-Hill, 1994.
Here are some helpful books on NFS and NIS/NIS+:
Eisler, Mike, Ricardo Labiaga, and Hal Stern. Managing NFS and NIS. 2nd ed. Sebastopol, CA: O’Reilly Media, Inc., 2001.
Olker, David. Optimizing NFS Performance: Tuning and Troubleshooting NFS on HP-UX Systems. Upper Saddle River, NJ: Pearson Education, 2002.
Ramsey, Rick. All About Administering NIS+. 2nd ed. Englewood Cliffs, NJ: Prentice Hall, 1994.
Sun Microsystems. System Administration Guide: Naming and Directory Services Nis+. Lincoln, NE: iUniverse, Inc., 2005.
Usenet users can find out more information on client/server computing under the newsgroup comp.client.server. There are a number of FAQs (frequently asked questions) on the issue of client/server computing in the UNIX environment. If you want to find out more about NFS in newsgroups, try comp.protocols.nfs.
There is also a useful web site explaining client/server evolution at
http://www.compinfo-center.com/apps/client_server.htm
and two FAQs pages at
http://groups.google.com/group/comp.client-server
and
http://www.faqs.org/faqs/client-server-faq/.