The Quickstart and Testsite packages are no longer maintained the way they were. In the future, we hope to provide them as easy to use T3D packages to be imported into a dummy site, but in the meantime you can still download older versions of the packages from sourceforge. After having installed those old quickstart/testsite packages, you can easily upgrade them following the steps in the upgrade guide on wiki.typo3.org.
TYPO3 has a large and growing community of users worldwide. The majority of users seems to be from Germany for some reason not totally discovered yet. Somebody has said that it must be because Germans have this sense for quality... :-)
Anyway, we are ultimately neither based in Germany, nor Denmark but internationally. The official TYPO3 language (apart from TypoScript...) is English. All communication on developer level is required to be in English, that's how we build a shared base of information for everyone to use.
This website and the mailing lists are the boiling points of the community, but the IRC chat is important, too. Here, people meet in cyberspace to help each other and discuss new development. Get a login ASAP.
There's also a Blog server called Buzz that can give you another point of view from the TYPO3-peoples.
The TYPO3 Extension Repository (TER) is the backbone of contribution. Extensions are a far-reaching concept allowing people to contribute everything from highly complex additions or modifications to TYPO3 to simple skins or documentation and tutorials. The TER also offer a possibility to not get lost in this huge project since you can clearly identify the parts of TYPO3 interesting to you and then communicate directly with people of similar interest.
Each year we meet in the real world on snowboards. This event is highly catalyzing for the events the rest of the year and it's highly recommended to participate. Don't be shy - go!
User groups are emerging in many places, particularly in Germany. See this page for TYPO3 User Groups (TUGs). Please also tell us if you want to take some public initiative. If you are planning TYPO3 related one-off meetings or seminars let us know as well, and we will publish the news on this site!