Ann,the suggested fabrics are listed on the back of the pattern envelope. I can no longer read what's there, but basically you need to use a soft, drapey fabric. However, no crinkle fabrics and don't use slinky or slinky-types for the first pair. I have 3 pairs cut out - wool crepe, untextured tencel, and rayon challis. I had a piece of linen designated for OneSeams, but so far, the washing hasn't softened it enough - it's still too stiff. I also have a knit faux suede that will work well, a heavy sueded rayon, and a few others that I've forgoten the names.
I do not think you'll find much suitable at WalMart, though sometimes their selections surprise me. You may need to try some of the internet vendors. One that I can recommend is Julie Culshaw at
http://www.timmelfabrics.com She will send swatches and she also has a toll free number. Louise also sells suitable fabrics, but you'll need to call or email her as I don't think they're on the website. Do make a trial pair first. I have found the inseam to be too far forward for my liking and still need to play with the pattern to change that. Otherwise, I love the pattern, the instructions, and the ease of making these pants.
At one point, someone - maybe Louise - posted a way to test the fabric while in the store. I don't remember the particulars and so far haven't found it in the files that I saved.
Julia in Houston