I always use Sam the Tailor, just off Nathan Road. There may be better, but stuff I bought from him years ago is still going strong.
Ned Kellys in Kowloon is a good bar, and you'll find it easy to get to talk to people there. It's not a big place, but the jazz is ok.
You'll probably run out of time to do everything that there is to do in HK, but be warned about shopping for electronics-it's not the bargain centre that it used to be!