I love the OBW, I just finished two myself, feel free to ask anything along the way if you are stuck. I have just done the hexagon one and not the octagon one. THey are a little different but not much, it is a really easy one to put together.

In addition to buying the book, I would also recommend buying the triangle ruler to help you cut your blocks and consider buying the mirror to help you audition fabrics.

I took a class at my LQS for kaleidoscope quilts. It was a lot of fun and I actually got 8 blocks finished in class.

Have a question. Once a cutting board gets warped from the heat, such as having left it in the car for a few hours, is there a way that it can be flattened out again? Happened to a friend of mine and she asked me what could be done to flattened it out again. I told her I would post the question here, for you gals just about have all the answeres, your a super bunch.

What kind of mirror would you be referring to?

I would imagine you COULD do OBW either way, but machine would probably be faster. they have little "hinged" mirrors in the quilting section you can sit by a design and get a "multiple" view to kind of see what a kaleidoscope of the design will look like.
There are some "design in the design" for OBW's the book I have shows how to make 3-D kind of squares within your hexagons.