Greets, fellow enkafan!
I'm a Kitajima Saburo fan from way back. Second to him, it's a tie between Sakamoto Fuyumi and Yoshi Ikuzo.
Hono; no Otoko was the first song I learned in Japanese, followed closely by Yosaku, Matsuri (da), Hakodate no onna, Yuki guni, Sake yo, Abare daiko, and (as a blast from the past) Akogare Hawaii no koro.