I do NOT know of a way to MASS PM. I sat down once and searched out each individual and did a LOCAL Reminder for Carlisle. It was more work than the end result.
The best way to get an "INTERESTED" person information is to post it!
Like I say, if "INTERESTED" they should look in that topic area and will get the information.
To get information "NOT REQUESTED", no matter the topic, is spam.
We all get enough of that.
I know your intentions are good, but lets honor everyone's privacy.

- JD