here are some things:
there is a really great bar in shibuya called JBS, the bartender basically sells beer and other drinks out of a cooler and plays his extremely expansive jazz, blues, and soul vinyl collection. i heard some really great music when i visited!
also! not in the center of shibuya but in the shibuya city limits there is commune press, a great gallery/zine publishing store front! they have all sorts of fun art objects.
waltz is a dream, my friend and i probably spent over an hour and a half there. sweet folks, great selection of tapes and records both used and new, lots of really cool books too! plus, nakameguro is a beeautiful part of the city! it is totally worth spending a full day there! we grabbed some pasteries at this little spot called gentille that day too!
like others have said – take it all in!!