Definition of a nice piece varies a lot so you need options. For twiggy type stuff, look for some place where people dump their brush where it may lay for years to dry out. Places where creeks or rivers flood often are my favorite.
I just got a decent malaysian order from DrFostersSmith. I've purchased manzanita from http://www.manzanita-driftwood.com/Manzanita.html as well. Buy 2 get the 3rd free is a pretty solid deal, especially when you're scaping a large tank or have multiple tanks to scape.
The malaysian order I got from DFS was pretty solid, 4 unique pieces and 3 average 'driftwood' pieces.