Although I could go on indefinitely, I will cover only two more knitting-related locations in Manhattan before I head over to Brooklyn (and back to pure yarn stores). The two last stores I have chosen are both New York institutions.
M&J Trimming (1008 Sixth Ave, New York, NY 10018, 1.800.9MJTRIM, http://www.mjtrim.com/), which was founded in 1936, carries products from all over the world: ribbon from France, lace from Switzerland, Swarovski crystals from Austria, buttons from Italy...
The store has a huge inventory of trims, fringes, lace, ribbons, tassels, buttons, rhinestones, beads, buckles, clasps, and more, both online and at the New York showroom. The MJ website is an institution in and of itself. It's extremely well-organized and very much like the actual store: you really see every detail and know exactly what you are ordering.
MJ's founder, Michael Cohen, started out selling linens, but when a patron left some lace in his store as collateral for a loan, Cohen found out that there was great potential in selling trimmings: so many of his customers wanted to know where he had gotten the lace that he forgave his friend the loan and asked him to get him more lace instead. The rest is New York history.
A family business, the store was taken over in 1956 by Joel Cohen, Michael's eldest son, who made the window displays known all over town. It is now run in part by his grandson, Michael J. Cohen (the current Executive Vice President). With 5000 square feet of merchandise, it can take a good two hours to digest everything. The white ribbon wall alone can leave your head spinning!
MJ Trimmings is full of useful items and extremely well-organized. The staff is very knowlegeable and friendly. All items are on display and easily accessible. There is a whole section in the back for brides. A Bridal Specialist will present you with samples of veils and gloves. You can work off of the samples to make decisions about style, cut, color, length, lace, crystals, and edging. The customized veils and gloves are then hand crafted by MJ Bridal Designers. (I had to throw this in, because I am still--after seven years of marriage--obsessed with weddings!)
What I missed at this store is the "small store feel" of some of the other locations I've visited. MJ is a huge place, where the staff wears uniforms (MJ t-shirts, which make them easily identifiable, but also give a bit of a corporate feel to the place). It is, however, unbeatable in terms of what is available and how easy it is to find things.
And there are lots of pretty, shiny Swarovski crytals!