Advanced STL Programming - A course for experienced STL programmers, offered by Semantics Consulting, Inc. - http://www.semantics.org/courses/Advanced-STL-Training.html
Phil Ottewell's STL Tutorial - A tutorial about the C++ STL, suitable for readers with C++ experience including examples and working program samples. - http://www.pottsoft.com/home/stl/stl.htmlx
STL Manual and Source - A downloadable manual for STL and pointers to a faq and source for an implementation of the STL. - http://www.cs.utexas.edu/users/lavender/courses/stl/
Microsoft MSDN: Standard C++ Library Reference - The Online Reference for the Microsoft STL Library Implementation at MSDN. - http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vclang98/HTML/stdlbhm.asp
An Introductory STL tutorial - Hosted on The Code Project, this tutorial gives a basic introduction of the concepts of the STL. - http://www.codeproject.com/vcpp/stl/stlintroduction.asp
A Tiny STL primer - A short description of the STL by David Harvey with links to other pages. - http://academic1.bellevue.edu/cpphome/stl/tiny_stl.htm
STL Tutorial - A STL Tutorial including some graphic explanations. - http://www.decompile.com/html/tut.html
A modest STL tutorial - Contains an introduction to the concepts of the STL. - http://www.cs.brown.edu/people/jak/proglang/cpp/stltut/tut.html