You can get in direct contact with the debexpo team. In case of technical problems please check the Q & A section and the Debian wiki first. Please do not use this contact address for sponsor requests or packaging questions, write to the debian-mentors mailing list instead or file a RFS bug respectively.
Currently Baptiste Beauplat (lyknode), Mattia Rizzolo (mattia, IRC: mapreri) and Paul Wise (pabs) are maintaining this service.
We are always looking for new contributors. If you want to contribute or improve mentors.debian.net, come to #debexpo on irc.debian.org and chat with us.