hey, there.
You cannot use just any wood you find, for most kinds of wood will rot and degenerate when exposed to water for a long period.
Plus you have to watch out that the wood may contain toxins that may leak into your tank.
I think your best option is just to invest a couple of bucks and buy a nice piece you like at a LFS.
That way you'll be sure it's aquarium-safe.
Using "wild- caught- wood" is not worth the risk.
I catch your drift, when it comes to a centre-piece of wood in your tank.
I got this piece on a secondhand site, and bought it for 25 Euros in my hometown.