inching over

Hey, does anybody know how I can get the layout here not to have that extra blank space over there on the left (or at least not so much of it)? I'm still using the "classic" template because the newer ones are no good (e.g., the polka.dot.dot.dot part gets cut off). I've tried fooling around with it and successfully made the "main" section bigger today, but any bigger and the left sidebar disappears for some reason.

. . .