Support department – firstname.lastname@example.org
User guides - kilgray.com/resource-center/user-guides
Training videos - kilgray.com/resource-center/training-videos
Regularly scheduled live webinars - kilgray.com/news-and-events/webinars
Recorded webinars - kilgray.com/resource-center/recorded-webinars
Trainers list - kilgray.com/resource-center/trainings/trainers
Translators Training basics video - translatorstraining.com/mat/presentazioni/Memoq.htm
memoQ Yahoo! group (English) - tech.groups.yahoo.com/group/MemoQ/
memoQ Yahoo! group (German) - de.groups.yahoo.com/group/memoQ_de/
Marek Pawelec’s blog (English & Polish) - wasaty.pl/blog/tag/memoq/
Translation Tribulations blog - translationtribulations.com/search/label/MemoQ
WikiBooks - en.wikibooks.org/wiki/CAT-Tools/MemoQ
There are also assistance forums on commercial portals and professional association sites. The value of some of these is severely limited by policies affecting user privileges, access and expression.
If there are other worthwhile resources in any language that I've missed, please feel free to add them in the comments.