Joann's here in Houston has tons of adorable flannel prints at good prices.

I've made a rag quilt with flannel and cotton squares for the front. I did wash and preshrink all the fabric because the flannel will shrink more than the cotton. I did sew an X in each block, after the quilt was done I washed it several times to get the raw edges to ruffle. It turned out nice and I could not see any difference in the ruffling of the flannel and cottons, it all blended together nicely.