If this was a popularity contest, Ivan Terrazas, better known as Baby Ketten, wouldn’t crack the top five. If it was about showmanship, he wouldn’t even make the list. But Ketten’s songbook might be the best in the country, let alone Seattle. I’ve sung up and down both coasts and at many points in between, and he has selections I’ve never seen (and know I never will) anywhere else. While that may not matter to the karaoke fan happily belting “Don’t Stop Believin’ ” for the thousandth time, for obsessives like me, the opportunity to find deep tracks means everything. Go see for yourself every Thursday through Sunday at The Spectator. JEFF ROMAN The Spectator, 529 Queen Anne Ave. N., 599-4263, babyketten.com