I learned Go as a kid, and played in a Korean Go club near my house. Then people in college started playing and I fell in with 3 other people, all around the same rank, though I played faster. Then I read _In the Beginning_ and pulled ahead a bit. Later I went to the San Francisco Go club for a while, and later yet the Indiana University club. Around 2005 I started playing and studying more, because of Hikaru no Go, mostly playing on KGS. 10k there, estimated 12k-10k AGA rank from club experience. I might be a weird amateur, with more fuseki than joseki, tsumego, or fighting confidence under my belt. Accounts are mindstalk and mindblitz (for blitz play) on KGS, mindstalk (no real rating yet) on IGS.
Actually, the other part of my "pulled ahead" was noticing that a lot of my games -- even games -- end up with my having small separated corner and side territories while my opponent had walled off the center plus some side. I had groups, he'd have 4 or 5 walls working together. Oops. _In the Beginning_ probably helped -- teaching 3-3 and third line 2-point extensions -- but a big deal was a commitment to breaking out and destroying center territory. Marching kosumi worked pretty well.
Most recently I've been studying tsumego, both problems and playing with positions (cgoban2 is *so* convenient.) I need to review my games a lot more, I'm sure, and study some high-dan ones.
I play chess somewhat, and know shogi rules but haven't ever really played. Go seems to have much more explicit naming of concepts and positions than I've seen in chess -- either that or more concepts.