A collection of Frequently Asked Questions and their answers is maintained by Kurt Hornik and can be found at the URL
http://CRAN.R-project.org/doc/FAQ/R-FAQ.html
Thanks to Martin Maechler there are a number of mailing lists which are used by R users and developers. See
http://www.R-project.org/mail.html
for details.
The Comprehensive R Archive Network (CRAN) is a collection of sites which carry identical material, consisting of the R distribution(s), the contributed extensions, documentation for R, and binaries, with the master site at http://CRAN.R-project.org/ and information on daily mirrors available from
http://CRAN.R-project.org/mirrors.html
R has a bug-tracking system (or perhaps a bug-filing system is a more precise description) available on the net at
http://bugs.R-project.org/