Order Marci's new book, ABC 3-D. I do not have it but it has the same techniques in it.

I am pretty sure that Crafty's BOM 2013 workshop (Free of charges) is going to deal with Tumbling Blocks without Y seams. Also I found a Marci Baker Tutorial on the internet re tumbling blocks with enough info to master the technique and make a cot quilt. I would add a pic if I knew how???

If you belong to a quilt guild they have library's and may have the book you are after.

Each block is made from 2 60* diamonds and an equilateral (60*) triangle. (plus seam allowance on each) Select your size, and cut with your ruler. what is special here is that by using 2 triangles, you have no Y seams and piece in columns. As with all building block quilts, the 3 d effect is achieved using 3 values of fabric. Generally, the light is on the top (triangle) and the medium and dark are in the same relative position throughout the quilt.