I came across a provider who was on Linkedin. That just seems like a colossally bad idea to contact a provider from your Linkedin account. Your business contacts can see that you are connected, and Linkedin tells you who has viewed your profile. Scary.
I second that recommendation. My Yahoo and Gmail accounts automatically save any sent/received addresses as a contact and when Facebook, Twitter, LinkedIn, Spotify, etc asks you to "see if any of your contacts are on _________", you might find yourself - your REAL self - receiving friend or follow requests from a hobbyist or provider.
I have ran across many Provider's real life profiles when these social sites mine my contact lists. Once you provide FB, Twitter, Spotify, LInkedIn, etc with the same email address as you Hobby with, you definitely lose your anonymity. I would never use an email account for any of the social marketing sites that is or has been used in Hobbying activities. As a matter of practice, I open a "disposable" email account for each social marketing site and never use it for any other purpose.