goto Mong Kok, thats where locals go for heavily discounted stuff
all my computers, electronics, clothes, phones, big boyz toys, car parts and fishing gear of course were bought from there i don't know the street names but i suggest explore all of Mong Kok. I reckon for a first timer, it'll take a day and it'll be worth if you love your shopping. Avoid buying stuff in tourist areas like Tsim Sha Tsui because they'll rip you off. But still take a look though. Suggest you buy a pocket map for $20HKD from the airport. Otherwise Mong Kok looks like a mess
Buy lures! My friend got heaps of quality Japanese squid jigs real cheap. hk is like japan out of japan, so you'll basically see quality japanese gear. don't be surprised to see big game gear too!
I suggest shipping some gear...postal is cheap. i always ship the stuff that check-in won't allow me to carry.