Starting at the bottom of
Union Square, you'll find the famous
Virgin Megastore. Inside you'll find a large selection of music and quite a few listening stations so you can check out the music before you buy it. In the back, you'll find a little café where you can rest your weary feet with a cup of coffee. Down the escalator is the more obscure music, as well as books and clothing. Be sure to check the bargain bins by the upstairs register for good deals. If you're really lucky, you'll catch an in-store appearance of an emerging artist.
Head west and notice Shoemania, carrying all the hippest sneakers (Puma, Adidas, Merrell, etc.) and also comfort shoes (Dansk, Birkenstock, etc.)
Next door you'll see the new and happening Whole Foods. If you're just visiting, go straight to the back and pick up some prepared food. You can eat upstairs or outside.
The next big store/complex is DSW and Filene's Basement (ironically upstairs). DSW is New York's biggest discount shoe store. They carry something for everyone! Along the wall you can find Lacroix, Marc Jacobs, and more. For bigger bargains, go directly to the back racks. I found some awesome Cole Haan/Nike boots for my boyfriend at half the price.
Filene's can be hit-or-miss, but it's definitely worth the treasure hunt. I got my brother some really cool French Connection Jeans half off the retail price. Women have an entire floor to themselves and carry various name brands. The top floor has house wares and luggage. The luggage is really worth it since they are top name brands at a much better deal, especially when on clearance.
Starting up north, you'll see the Diesel store (smaller than the flagship up on 60th). Jeans here are probably the coolest around (for guys; I can't fit my butt into the female jeans); however, they can run up to $250 a pair. Run downstairs to see if you can find some on sale. (Always check Filene's first, since they sometimes have Diesel jeans on sale).
The next store, Mexx, is originally a popular Belgian store that came over to the states not too long ago. It's had nominal success and carries some decent stuff. Since it's not all over the US quite yet, you can at least buy something that no one will be wearing in your town.
Take a left on 16th Street over to Fifth Avenue. There you'll see Anthropologie, a store under the same company as Urban Outfitters. It carries more mature clothes, but they're still very whimsical and beautiful. Most clothes are reminiscent of older eras. This season, I'm seeing a lot of Victorian-looking clothes with high necklines, poufy shoulders, lace, and velvet. If you like interesting clothes and unusual cuts and fabrics, you'll enjoy shopping here. They also carry house wares and linens. Downstairs is where all the sales racks are kept.
Across the street is Esprit, back from Europe with a sizable flagship store. They have a teen line called EDC that has younger, trendier clothes. Esprit for Women is professional, with a hint of glamour. They introduce some more interesting clothes than Club Monaco, GAP, and Banana, and are sold at a reasonable price.
Also on Fifth Avenue, you'll find Kenneth Cole, Fossil, and Daffy's. Daffy's is a New York-exclusive discount store that carries a lot of strange European-brand clothing. It's a bit of a nightmare to shop there, but once in a while, you come across some amazing Italian clothes at a really low price. Dig around if you have time.
Also by Union Square, on Broadway and north of 16th, is the sports store Paragon. This store is very old-school New York (you'll see what I mean when you walk in). You can find polo and Lacoste clothing here, as well as bathing suits, skater shorts, and sneakers downstairs. It's basically a bit higher-end than the Sports Authority.
Finally, the ABC home and carpet store takes over the rest of the block. I have a full description of this store in my Brooklyn entry. It's a few stories of absolute luxury. You can't miss walking through this overpriced, yet beautiful, store.
On the north side of Union Square you'll find a Petsmart and a fairly large Barnes and Noble. Finally, in the center of it all is an organic market that runs all week long during the day. You can find fresh vegetables, wool yarn, flowers, fresh bread, fresh cheese, fresh game, etc. In the winter, the stands all have apples and warm apple cider.
*Please note that Mexx and Esprit is slated to move to SoHo. Check the websites for latest information.