Note: Before you contact us to report a bug, request a feature, or ask for help with installing/playing STK, it's worth checking our FAQ.
Official forum This is probably the best way to contact us, and get in touch with the STK community. Feel free to discuss your ideas, ask question, offer help, ... there.
If you are impatient, or like real-time action better, you can use our irc-channel #supertuxkart on freenode, which can also be used online. We're not there 24h though so you may not get an answer, but it's always worth a try.
A mailing list is simply a list of various e-mail addresses, aliased under one e-mail. This means you can send an email to the list address, and everyone signed up to the list will get your message.
Our project at github
Our home at sourceforge