If you want some nice driftwood you can see before you buy it, try eBay. The user Rockartsource usually has a nice listing of various sizes, the majority of it sinks without the aid of slate.
Don't bother with that junk. Yes, I bought it from BigsAlOnline. Mine started to dissolve everytime I touched it until I just threw it out. It also took forever to sink even with the attached slate. Maybe it was the boiling, to get it to sink, that made it fall apart so quickly. Who knows? You'd be better off with something else though that's for sure.
Malaysian driftwood is one of the better choices. It always sinks on its own, is available in all manner of funky formations. And if it colors your water, it does so with a nice amber instead of yellow.
