an excellent question!
i think that most of what i have learned has been through others for sure, particularly from forums and groups, such as this one. i have known always that i was submissive, before i even knew what it meant. and i knew that i craved being dominated by someone before i even knew there was a term to describe not only that, but that type of relationship.
of course, through trial and error and experimentation, i was able to discover some things on my own with previous boyfriends and such - some light bondage here, a sensory deprivation there - but really, it has been through magazines and online research that we have really grown in this lifestyle together, my Master too as this was all new to Him at the time.