Here's a previous post of mine too!
Where to begin... For starters, you'll see many camera stores, but don't be tempted to buy just anywhere. You want to make sure you buy from somewhere reputable, but without paying top dollar with the bigger chains.
I don't know your nationality or language capabilities, but there's usually room to haggle everywhere in Hong Kong even if fixed prices are shown. If you're buying lots, ask for a discount.
For buying camera equipment, I'd suggest
Tin Cheung. You'll find them located in
Carnarvon Road, Tsim Tsha Tsui. Just take exit D1 out of the TST MTR station and it's just about 100-metres away. I bought a tripod and a number of lenses from there and haven't had any problems. Some were grey market (no warranty, but much cheaper), my L lens came with an optional international warranty.
From there, it's only a short walk away from TST promenade where you can join everyone else to photos of the Hong Kong waterfront.
If you want to, you can get free access to high floors in the Bank of China building and IFC2. Just take your passport along with you for ID and you'll get an amazing view of all the buildings around central Hong Kong.
No doubt, you'll visit Victoria peak. I'd suggest taking a tripod and going late afternoon about a couple of hours before sunset. You'll have time to walk around to take photos, but also enough time to get a good spot on the sky terrace (pay the extra when you buy your tram ticket as it's a bit cheaper, but beware it's single use) to get the night view.
If you time it right, you can catch the open-top bus from just outside of the tram station and it'll take you on a fantastic night-time tour around central Hong Kong to arrive near the Star Ferry terminal. Then, try to catch the ferry so you're crossing whilst the Symphony of Lights is on (between 8pm and 8.15pm each evening) for a less crowded view of the performance.
If you want to escape out of the busy city, then check out the numerous
parks Hong Kong has to offer. They're all free and very well looked after.
I'd suggest buying your memory cards before you get to Hong Kong as prices weren't as good. I'd also suggest an external hard drive was a necessity, but you might not need one for a short stay. I shot over 2,000 photos in RAW so I'm glad I took one.
Get yourself an Octopus card as soon as possible. It's like London's Oyster card only it's accepted on almost every mode of transport and even in some shops. You can buy one from any train station or at the airport. Prices start from HKD$150 (cash only) with HKD$50 going towards the refundable deposit on the card itself. Absolutely essential piece of kit.
The Mass Transit Rail (MTR) trains are very easy, fast, clean, cool, reliable and are usually the main form of transport for locals and tourists alike.