If you came to this page because you want to learn smalltalk, you'll be disappointed. GNU Smalltalk is designed mostly for scripting. Anyway, here are some links and document's you want to look at:
- Squeak swiki
- Free smalltalk books.
I like "Smalltalk by Example most - however, it means learning by doing, and you should have a basic idea about smalltalk
The GNU Smalltalk tutorial ("info gst" of, if installed, "pinfo gst").