There are many resources available for those who need help with Mailman, beyond the on-line documentation. If you are having problems installing or configuring Mailman, you should probably start here:
You should also check out the community driven wiki, which hold the most up-to-date information about Mailman.
Beyond those resources, please use the discussion lists for asking questions. There are lots of very helpful and knowledgeable people on the lists who can help. Probably the most helpful will be the mailman-users mailing list.