Nancy Ann -- I really wanted to try to use repo fabrics and a nice Kona off white cotton. When I visited quilt stores, I always asked about Civil war prints and only bought fat quarters. Nearly all the blocks are kona and one print, but only a few are two colors. I did graph out how I wanted the coloration to be similar to Jane's. You can see the pink in a diamond, red, green, etc. and I wanted mine to be like that one.
Now that I am on the borders, I am using the fabrics from the blocks for those -- not buying more fat quarters, and I am mixing up those fabrics. If you want to buy an entire bolt of your background fabric I would certainly do that due to dye lots and color changes or go for scrappy. But if you do go with one background get plenty -- I thought I did and still ran out on the 4th border.
Hope this helps, thanks for the lovely comment on my DJ.
Sharon - we're waiting for company from Nebraska tonight for the weekend