Markos Markopolous - his internet evangelising and the old PTC newsletters got me interested in real strength training, not doing babby's 5 day split like all the other bros, it gave me a sense of direction when I first started training (and it's how I found AusBB).
Rippetoe, not from a programming point of view and I'm not a fan of his squat method, but his videos are overall useful
Jonnie Candito - had been spinning my wheels with squatting, deadlifting and 5/3/1 in general, I found his form videos to be exactly what I needed, and have made good progress with his generic programming.
Honourable mention goes to the competitive PA lifters I've spoken to or trained with in person.