The Network Book - A comprehensive introduction to network and distributed computing technologies - online - http://www1.cs.columbia.edu/netbook/
The Internet Companion - Online version of the book "The Internet Companion". This book explains the basics of communication on the Internet and the applications available - http://archives.obs-us.com/obs/english/books/editinc/
Internetworking Multimedia - This is a online book covering multimedia communication using the Internet - http://www.cs.ucl.ac.uk/staff/jon/mmbook/book/book.html
Understanding Networking Technologies - Online course providing training on a host of networking topics. - http://www.netguru.net/courses/ntc/tblcont.htm
Bill Stallings - Author's site. - http://williamstallings.com/
Troubleshooting TCP/IP - This is a sample chapter from the book "Windows NT TCP/IP Network Administration", published by O'Reilly and associates which explains how to solve problems related to TCP/IP in a Windows NT environment - http://www.oreilly.com/catalog/wintcp/chapter/ch11.html
TCP/IP Network Administration, 2nd Edition - Clearly written, this book is a good introduction to the TCP/IP protocols and practical applications. - http://www.oreilly.com/catalog/tcp2/noframes.html
Douglas Comer - This is the home page of Douglas Comer, the author of the book "Internetworking with TCP/IP". - http://www.cs.purdue.edu/people/comer