What kind of wood are you looking for? Manziman sells amazing manzanita wood. Betta factory on amazon and eBay has great Malaysian driftwood. Haven't found a good mopani vendor yet
Pretty much any wood is going to float unless you buy it pre-soaked. Some will take longer than others to sink though, I think.
My manzanita only took a few days to a week. Malaysian..I have a piece that I've had since august or so? Not sinking.It is really thick though.
(one on left)I just got 6 new chunks of Malaysian I put in my tank yesterday. They all sank instantly. Manzanita typically takes < a week. I never presoak or boil any of my wood