Maintained by the great Franck Arnaud, this is the must-see source
of information. You can get an up-to-date version of the
Eiffel FAQ here.
The Eiffel Newsgroup
The Usenet newsgroup dedicated to the Eiffel language is
comp.lang.eiffel
EiffelZone
The EiffelZone, maintained by Roger Browne,
is a very complete and up-to-date source of Eiffel software and libraries. Roger deserves many
cheers!
Eiffel Books
Design
Patterns and Contracts, by Jean-Marc Jézéquel, Michel Train
and Christine Mingins. A very good book, with plenty of examples
to compile with SmartEiffel!