With very little effort on my part, all sorts of fabulous insights and information come to me from the collective experience and expertise of its participants. I belong to several discussion groups. I learn what concerns others who share my professional interests. I learn innovative practices and how others solve problems similar to my own. I hear about seminars, workshops, conferences, etc. in my field.
Members often share citations for significant articles and books.
Here is a site for a comprehensive catalog of discussion groups in human resources. Your text lists dozens, many of which are held in a local academic library. Remember that even if you don t have a personal subscription, most college and university libraries will let you read their materials in the library. Your tax dollars pay for the resources. Many of the highest quality journals are those produced by societies, associations and of practitioners within a field.