I discovered Palestinian embroidery at the fantastic Palestinian Costume exhibition at the old Museum of Mankind in London. in 1989. To tell the truth, it was this exhibition that made me aware of who the Palestinians were, and what a beautifully rich culture they possessed. The catalogue to this exhibition is still quite easy to find, look on Abebooks.
In 2007 I found "Palestinian Embroidery Motifs:A Treasury of Stitches, 1850-1950" , by Margarita Skinner and Widad Kamel Kawar, in the bookshop of the Victoria and Albert Museum. This is a fantastic book: photographs of a collection of stunningly beautiful dresses, technical and historical commentry. and over 200 motifs named, located geographically, and drawn up in diagrams that are easy to sew from. An unusual combination of a beautiful record and description, and a very practical guide for sewing. My copy is falling apart.