Are these blocks made with triangles or octogon shapes? How do you sew them together? Is there a tute on this board available?

You make them with triangles, but the angles on the triangles can be such that they form either a hexagon or an octagon when put together. If they form a hexagon, the hexagons fit together with no additional fabric. If an octagon, you have to add "corners" to form squares before putting the blocks together. Both are explained in the book One Block Wonders by Maxine Rosenthal. Most of the ones I have seen on the board are made with 60-degree equilateral triangles, forming hexagons. You start by sewing each half of the block together, then decide where to put each block on a design wall, then sew the quilt together in strips consisting of half-blocks. I highly recommend the book, or one of the later books by the same author.

There is a class here that cutebuns taught us, called tiptoe through the hexagons, cutie style. She explains in a series of topics how to choose the fabric, cut, sew, and layout the blocks :D:D:D

There's also a topic list here on the board, http://www.quiltingboard.com/virtual...jsp?vsnum=1006 here you'll find all the OBW and stacknwhack threads in one place. I've only made the hexagon ones myself but the octagon ones are also explained very clearly in the first of the books that dunster mentioned.