Help gaining knowledge on SET

I live in an area where there not many dealers and there are no dealers of SET. How can I find out more info on different types of SET amps/tubes and their sound, SET vs SEP and SET vs SE parallel amps. I really want to get into a SET amp, but must do it site unseen. Before you respond I have had a 300b and that is definitively not my cup-o-tea. My speakers are 92 db, 8ohm so no problems there. Are all SEP amp ultra-linear? Lots of questions.
Thanks