what ScottC said... you may also try Broadway stores.

Bunch of stores along Sai Yeung Choi St (parallel to Nathan Rd.)

If you are adventurous, you can try 'Sin Tat' (Sai Yeung Choi and Argyle Sts I think). Whole building of little phone shops for both new and used phones.

Warning: Shops and streets get packed from the Mainland folks.


just for comparison, I saw the O2 mini there last month for ~ $HK4000

Let me know what you find for the 9100 (or iMate Jam). It's a sweet phone.