A couple weeks ago I stumbled across a huge wholesale Asian foods warehouse in Hicksville, Long Island that's open to the public. It beats anything that I've seen on LI and even gives anything in Flushing or Chinatown a run for its money.
JV Trading Ltd.
(web presence at www.orientalfoodmaster.com)
385 West John Street, Hicksville NY 11801
It's on the south side of West John Street between the LIRR/Post Office and Agway. Coming from the LIRR/Post office, look on your left and if you've passed the Agway, you've gone too far. It's tough to find since it's tucked away on the side entrance of a non-descript warehouse building.
This place is fantastic! It has everything from a thousand varieties of soy sauce to otherwise-impossible-to-find-on-LI fresh Asian noodles in the fridge to fresh veggies and seafood. You're basically walking the aisles of their wholesale warehouse, so be prepared to be a bit overwhelmed.
If you visit, bring your coat. The place is a giant fridge :)
I don't know why these people don't advertise... I guess they concentrate on their enormous wholesale operation instead.