Gourmet in Queens?
re: Cheese Boy
Red currant jelly can be found in decent supermarkets. I'm pretty sure Key Food here in Astoria had it (Hero brand). If not, Berry Fresh Farm, a supermarket past Steinway on Ditmars definitely has it. I don't know much about the area you live in though.
Berry Fresh Farm
4326 Ditmars Blvd, Queens, NY 11105
32-15 Newtown Ave, Queens, NY 11102
22-15 31st St, Queens, NY 11102
I don't know about duck fat but all of the other items you mentioned can be found in many groceries in Ridgewood and nearby Lower Glendale.
I would recommend you check out:
58-22 Myrtle Avenue
Muncan Meat (closed Sunday)
60-86 Myrtle Ave
Morscher's Pork Store (closed Sunday)
58-44 Catalpa Avenue
59-29 Myrtle Avenue
Zum Stammtisch Pork Store (atttached to the restaurant—both closed MONDAY)
69-46 Myrtle Avenue
66-64 Fresh Pond Rd
The first four are all within easy walking distance of each other.
I've been to Cheese of the World and it's fine for cheese but it's a major hassle to park around there and a lot of the other items you mentioned are readily available in Ridgewood/Glendale (and they're cheaper than in Cheese of the World).
Parking in Ridgewood/Glendale is not that bad if you go in the morning on the week-end though Saturday is the better day since both Muncan abd Morscher's will be open.
Getting to this part of Queens from Nassau County is fairly simple thanks to the Jackie Robinson Pkwy (lots of people around here reverse commute to work out on the Island because of the easy access).
Good luck wherever you go!
Glendale is hungry...
69-46 Myrtle Ave, Queens, NY 11385
Muncan Food Corp.
60-86 Myrtle Ave, Queens, NY 11385
Cheese of the World
71-48 Austin St, Queens, NY 11375
58-22 Myrtle Ave, Queens, NY 11385
Morscher's Pork Store
58-44 Catalpa Ave, Queens, NY 11385
66-64 Fresh Pond Rd, Queens, NY 11385
59-29 Myrtle Ave, Queens, NY 11385
Echoing Paulomet, it depends on where in Queens. Based on the "or Nassau" addition, I'm guessing you're somewhere out east. Food Cellar is a gourmet market a la Whole Foods, with prices to match, but its LIC location might not be much of an improvement over Manhattan.
Food Cellar & Co.
4-85 47th Rd, Queens, NY 11101
Where in Queens do you live? There are plenty of ethnic places, you'd just have to hit a couple areas for what you need. I'm sure the board could recommend neighborhoods: Astoria (Steinway) for Arabic, Jackson Heights for indian, Kew Gardens for russian or bukharan, Flushing for chinese, etc.....