Good morning, Ron;
A response for you, sir: Thank you for forming the group. Yes, such a group was needed, but it had not occurred to me to even think about this obvious lacking, and to do something about it. Again, thank you.
While most of us probably think first of a bellows unit for extreme close-ups, or even perhaps a microscope, there are other more simple things we can use for this purpose. Just a simple set of extension tubes will bring this capability to any SLR camera. The TTL light metering systems will handle the exposure compensation for us. Even more portable and easy to use are the plus diopter supplemental lenses that can be screwed into the filter ring threads on the front of our lenses. The two element supplemental lenses available from Canon, Minolta, and Nikon are a little more expensive, yes, but there can be noticeable differences in what you get on your negative, and they do have the advantage of great portability and no exposure compensation requirement. Use a lens hood with them.
There are lots of things to talk about. The relative merits of bellows, extension tubes, and close-up supplemental lenses. Why would you want a lens reversing ring and when would you use it. Ring light electronic flash units. Light reflectors. Things for holding our subjects still while they are being photographed. Wind blocks. How to look through your camera when it is in an awkward attitude close to the ground. How do you hold the camera still when it needs to be close to the ground.
Photographing small things can be a real challenge.
Enjoy; Ralph, Latte Land, Washington