See if their contact info is on the WIKI. If so, reach out directly to them.
Post a message on the members only board requesting training. Put what area or machine you are requesting training for in the subject line. (e.g. I would like to be trained on the Tormach). In your message, include days and times you are available to be trained.
Go to the weekly meetings (in person or virtually). Many of the trainers are at those meetings.
Go to the specific area in Lennox. Many Champions and Trainers have their contact info posted in their areas.