In southwest VA there are numerous man made reservoirs. Most have camps and RV site all around them and you have to pay to get in between April to October. But during the winter I hit them all walking the shorelines. I have found some pretty damn amazing pieces that would cost 100 bucks easy.
My daughter and I went to a couple of lakes and creeks around here, and we weren't happy with what we found. I shopped around and bought an awesome piece on Etsy of all places ... much better than what the LFS had. Seller had done a 10% bleach drip and a good rinse, and that's it.
I bought dritwood from the petstore and it always has a thick hair algae form that I have to clean off. I would recommend boiling and soaking for a month before putting even store bought driftwood in the tank.
So a guy walks into a Pet Store
Guy: "I have Algae on my drift wood!"
Pet Clerk: "Take two Plecos and call me next week."