I belong to two different types of writer's groups, online and in person. There are a far greater number of the online ones though I am truly active in only a handful at most. It is easier to get a wide variety of people online because we can come together from anywhere in the world to share our ideas, suggestions and questions. There is a good chance someone will know how to answer almost anything you ask there because there are numerous skill levels, backgrounds and areas of interest within any particular group.
While my groups I attend locally do have the varying skill levels and backgrounds I have noticed that a large number of the members tend to be of a certain age group and because we all reside in one area, many for decades now, it can color the answers to the questions with a particular bias. I do enjoy getting to go and listen to a speaker, learn from others and the things they have been working on as well as share my own victories and struggles.
Either type of group can be a tremendous help when it comes to learning to promote yourself and your work. I tend to use each group as a place to ask questions pertaining to the type of promotion they are already a part of, i.e. online groups for online promotions, live groups for in person events. There are a couple cross over groups I am a member of as well including the Indies of Las Vegas group that I lurk around in online but also, when possible, will go get coffee and discuss local events or get suggestions.
It can be very intimidating to actively participate in groups especially when you are just starting out. I have been a member of many of these groups for over two years and I still struggle to come up with things to say or ways to become better known. I watch from a distance, commenting occasionally and when I am feeling particularly daring, posting something of my own. The important thing to know is that while there are a few members here and there that are not as helpful, most of us in these groups want to help each other and see as many people succeed as possible. We are all learning, practicing and together as a team we can make many writers successful.