This is my favorite place in Madison to purchase needlework supplies. There is another shop in town that sells similar items but I have had two terrible service experiences in two visits there and do not intend to go back.
Lynn's, however, is another story. The store is not the best organized, but there is ALWAYS someone there to help me find what I need. They have plenty of of everything, from common branded fabrics and fibers to harder-to-find hand-dyed items. I can always find what I need...even if I can't locate it within the shelves myself!
Prices are reasonable, and Lynn's accepts debit/credit cards. They also have a ton of painting supplies (which isn't my area of expertise so I can't comment) and they also do custom framing.
Love the ladies at Lynn's!