There are many excellent autograph collecting clubs and discussion groups on the Web. These groups are organized in such a way that e-mails and message posts are exchanged between members instead of posting to a newsgroup. Since the majority of these groups are moderated (and the moderator approves all posts before they appear in the group), one of the advantages of this method is that the discussions are tightly focused on autograph collecting, and avoid the extraneous posts and spam (ex. "Make Money Fast...") that generally show up in newsgroups.
Most recently, I have been posting random thoughts about the hobby and information that is useful to the autograph collecting community at a blog that I have created. You can find it at http://www.collectingautographs.blogspot.com.
Yahoo Groups
There are many fine autograph collecting groups hosted by Yahoo, such as:
A1 Autographs
The Autograph Hound
Usenet Newsgroups
Usenet Newsgroups are discussion groups that are unmoderated and are grouped by specific topics. Below are some groups that I have found helpful in obtaining such information as addresses, signing habits and autograph show schedules. The nice thing about these groups is that there are some frequent contributors that are really helpful and give the groups a feeling of community.
alt.collecting.autographs
rec.collecting.sport.baseball
rec.collecting.sport.football
rec.collecting.sport.hockey