I've made a "woven" type wraps from Osnaburg that I really enjoy. I don't recall the specific tutorial, but I basically just bought 6 yards of the fabric, dyed it how I wanted (optional, obviously), tapered the ends a bit, and hemmed the edges. We've used it a fair amount, and it is still in good shape. I carry my 31lb 18-month-old in it still.
I've also heard you can buy jersey fabric and just use it as is, if you want a stretchy wrap. Apparently it doesn't fray.