There are a couple of good prayer shawl books in the stores - probably more, but these two have Prayer Shawl in the titles. They are so easy though. I use a basic pattern of about 24" wide by 60" long, then depending on the pattern you choose, CO on the number of stitches needed for any repeats. You can use any stitch you are comfortable with and if your edges are done in garter stitch (5 stitches at beginning and end of each row) your shawl won't roll on the edges. They can be as simple as all garter stitch, to very complicated cable or lace patterns. Why pay for a book when you could use the money for more yarn! Ravelry is a good source for free patterns, as well as many of the yarn manufacturer's websites. Good luck and don't forget to post photos of your prayer shawls.