Newsgroups are discussion groups based on Usenet (a worldwide distributed Internet discussion system) which are accessed using Newsreaders or different web interfaces like Google Groups. I provide links to the Google application here because it is easy to use and grants access to the archive of Usenet which dates back to the eighties.
comp.lang.modula2 is a Modula-2 newsgroup where you can get help. The archive of the group contains very useful information and also some pieces of code.
Other Modula-2 Newsgroups are inactive for a long time but the archives may contain interesting information. There are maus.computer.sprache.modula-2 and fido7.su.pascal.modula.ada, the latter being a group communicating in Russian language. Both groups have some useful information in the archives.
About 700 old postings from net.lang.mod2 are still available at Google's archives. This has been the predecessor of comp.lang.modula2 till 1986. Don't forget to search related groups for information. I found comp.compilers, comp.lang.modula3 and comp.lang.oberon useful as all of these groups offer a lot of Modula-2 related posts.
If you are interested in programming embedded systems, you may also want to search comp.arch.embedded.