For general questions please join the Grml user mailinglist (see below).
If you have found a bug please report it.
You can reach the Grml core team via team (at) grml.org.
For commercial support and services please send us mail to business (at) grml.org.
If you want to be notified when a new Grml release is available, subscribe to the read-only Grml announce mailing list.
If you want to participate in the mailing list of Grml, please subscribe to the Grml user mailing list. Anyone can post to this mailing list, but if you are not already subscribed, your message will need moderator approval before being posted. This way we limit the amount of spam that makes it to the list. The Grml user mailing list is available via gmane as well.
If you are interested in following the development of Grml you might be interested in the Grml developer mailing list. The Grml repository commits mailing list tracks all the pushed commits to Grml's git repositories, while we're also present on github. Changes in Grml's Debian repository can be tracked via the Grml Testing-changes mailing list. We track issues at github.com/grml/grml/issues. Several Grml sub-projects (grml-debootstrap, grml-etc-core, grml2usb,...) have their own repository and issue tracking, see github.com/grml/ to get an overview. If you're unsure where to report an issue though, feel free to use github.com/grml/grml/issues though.
Notice: All Grml mailing lists are English only.
You can find us in #grml on irc.freenode.org. Channel language is English.