If you're in need of, well, anything for crafts, this is your one stop in the city. I agree with some other reviewers that the layout is a pain, 5 floors with a very steep staircase, and a long wait for the elevator, AND you have to pay for your purchases on the floor they reside on. One nice thing they did - all the main hobby crafts (jewelry findings, Sculpey clay, sewing, rubber stamps, etc.) were moved from the 5th floor to their own shop down the street from the flagship store - on Lispenard between Church and Broadway. Makes it so much easier to get to and I've actually found the staff in this store to be quite friendly.
If you're a student, TAKE YOUR ID WITH YOU. I am a continuing ed student and they honor these, too. It will save you 10% off anything you buy at Pearl.
In the main store, they have everything you need for scrapbooking, pens, paper, glue, tape, paint, sketch books, poster board, paint brushes, anything! There's even a kids section on the main floor with big markers and fun things that might make good gifts for very young children.
If you need a bathroom, there's one on the main floor - key's at the main cash register. Just make sure you have some Kleenex with you.
2 other Pearl stores now across the street on Lispenard are the Frame shop (picture frames and supplies) and a more heavy duty shop that sells things you'd need for tiling projects.