I made this link collection 'international'. Here you will find links to both German and English websites (see the language-code in the squared brackets), which are IMO really useful. The information on these sites were a big help in a lot of situations. So I guess they will be interesting and helpful for many other Debian users too. Enjoy them!

Debian and Linux

http://www.linux.org [EN]
Linux Online
http://www.debian.org [International]
Debian.org - Homepage of the Debian GNU/Linux project
http://www.debian.org/support [International]
Debian.org - Support available to Debian users

Newsgroups, Mailing Lists, Forums

http://www.debian.org/MailingLists/ [International]
Debian mailing lists (information about available mailing lists, subscribing and unsubscribing such a list)
http://groups.google.de/groups?group=de.comp.os.unix [DE]
de.comp.os.unix.* Newsgroups
http://www.debianforum.de [DE]
German-speaking Debian forums

Documentation & Books

http://www.debiananwenderhandbuch.de [DE]
Debian GNU/Linux Users-Guide
http://qref.sourceforge.net [International]
Debian Reference
http://www.debian.org/doc/books [International]
Debian and Linux books overview

FAQs & HOWTOs

http://wiki.debian.org [International]
Official Debian Wiki
http://www.dcoul.de/faq/ [DE]
de.comp.os.unix.linux FAQ(s)
http://www.de.debian.org/debian-user-german-FAQ/ [DE]
debian-user-german (mailing-list) FAQ
http://channel.debian.de/faq/ [DE]
#debian.de IRC-Channel FAQ
http://wooledge.org/~greg/sidfaq.html [EN]
Debian SID FAQ
http://www.debianhowto.de [DE,EN]
Install and administer a server under Debian GNU/Linux (HOWTOs and manuals)
http://www.newbie-net.de [DE]
NewbieNet HOWTO-collection
http://newbiedoc.berlios.de [EN]
NewbieDoc project - a collecton of HOWTOs, also available als Debian package
http://en.tldp.org/ [EN]
TLDP - The Linux Documentation Project

These pages provide further links to other FAQ- and HOWTO-collections.

Kernel Building

http://www.kernel.org [EN]
The Linux Kernel Archives
http://newbiedoc.sourceforge.net/system/kernel-pkg.html [EN]
Creating custom Kernels with Debian's kernel-package-system
http://www.tldp.org/HOWTO/Kernel-HOWTO.html [EN]
http://www.linuxhaven.de/dlhp/HOWTO/DE-Kernel-HOWTO.html [DE]
Linux Kernel HOWTO
http://www.stud.uni-karlsruhe.de/~usge/kernel-compile.html [DE]
Compile your own Kernel under Debian GNU/Linux
http://georg.f-451.net/debian/kernel.html [DE,EN]
How to compile a kernel the Debian way? - a shot link collection for available HOWTOs

Graphics cards under Debian

The following links might contain outdated or obsolete information. Debian Sid contains official ATI driver packages (fglrx-*).

http://www.stanchina.net/~flavio/debian/fglrx-installer.html [EN]
http://xoomer.virgilio.it/flavio.stanchina/debian/fglrx-installer.html [EN]
ATI Linux driver packages for Debian

JAVA and Debian

http://wiki.debian.org/Java [EN]
General info about Java and Debian

Mail-Server

http://www.linuxer.onlinehome.de/apps/exim.htm [DE]
1&1 and GMX - multiple smarthosts with exim and AUTH (details about using fetchmail and exim with multiple smarthosts)
http://www.newbie-net.de/anleitung_imap.html [DE]
IMAP E-Mail-Server under Linux - build an email-server under Debian Woody with fetchmail, cyrus-imapd and exim
http://www.newbie-net.de/anleitung_fetchmail.html [DE]
Fetchmail - fetch e-mails for many users in an automated way (a short introduction)
http://www.schiessle.org/howto/debian-imap-howto/debian-imap-howto.html [DE]
FETCHMAIL-PROCMAIL-POSTFIX-CYRUS-IMAP HOWTO
http://workaround.org/articles/ispmail-sarge/ [EN]
Tutorial: ISP-style Email Service with Debian-Sarge and Postfix 2.1
http://www200.pair.com/mecham/spam/ [EN]
Debian Anti-Spam Anti-Virus Gateway Email Server using Postfix, Amavisd-new, SpamAssassin, Razor, DCC, Pyzor and ClamAV HOWTO

Debian-Packages

http://www.debian.org/doc/manuals/maint-guide/ [International]
Debian New Maintainers' Guide
http://www.debian.org/doc/developers-reference/ [EN]
Debian Developer's Reference
http://www.debian.org/doc/debian-policy/ [EN]
Debian Policy Manual
http://www.netfort.gr.jp/~dancer/column/libpkg-guide/libpkg-guide.html [EN]
Debian Library Packaging Guide
http://people.debian.org/~mpalmer/debian-mentors_FAQ.html [EN]
Debian-Mentors project FAQ
http://sponsors.debian.net [EN]
http://mentors.debian.net [EN]
Debian-Sponsors project - Search for sponsors or be a sponsor
http://wiki.debian.org/ [EN]
http://wiki.debian.org/BuildingTutorial [EN]
http://wiki.debian.org/PackagingTutorial [EN]
http://wiki.debian.org/MaintainerScripts [EN]
Hints and HowTos ~~by the Debian-Women project~~ about package building, involvement in Debian (packaging) ~~and the Debian-Women project~~ and becoming an (official) maintainer

Games and Debian

http://lhl.linuxgames.com/howto/half-life-HOWTO-0.5.html [DE,EN]
HOWTO run and play Half-Life using Wine
http://plug.ca/article.php?story=20020108132402283 [EN]
Unreal Tournament in Linux (without wine)
http://legendsthegame.net [EN]
Legends (a game for Windows and Linux)

Debian-basaed distributions and Live-CDs

LaTeX

Please use the Debian package tracking system for current LaTeX packages.

http://www.tex.ac.uk/cgi-bin/texfaq2html?introduction=yes [EN]
TeX Frequently Asked Questions
http://tu-dresden.de/service/cd/4_latex [DE]
TU Dresden (Corporate Design - LaTeX)
http://www.math.tu-dresden.de/~rudl/latex/ [DE]
Link collection for LaTeX (TU Dresden)
http://www.thesis-template.de/ [DE]
LaTeX and LyX templates

Special Links

http://www.linuxtag.org [DE,EN]
LinuxTag
http://www.linux-info-tag.de [DE]
Linux-Info-Tag Dresden
http://www.levenez.com/unix/ [EN]
UNIX history

debian.wgdd.de :: Link Collection