Yes, my best friend wrote a book about them. It is called, "Quick and Easy Hexie Quilts" by Dr. Peggy G. Rhodes and Julia C. Wood published by AQS. It has been a big for the past couple of years or so. AQS is doing a second printing. The book is really good and is illustrated in full color.
Julia came to speak at a guild I'm in & then taught a class the next day. I wound up taking the class too & what fun!
Of course I started a quilt & am working on it off & on but I still like regular hexies & am quilting one right now.
Have fun that's what we go for.