Hmm... Avoid any redwoods, Malaysian.... I have a Malaysian piece that super dyed my water xD I don't mind it though. I have neons so it adds a natural look and looks pretty cool ;)
I am thinking any pale woods would work, like birch. If you find driftwood, make sure to boil the daylights out of it to get rid of bugs, and any tannins it does have. Some woods can be left to soak to remove tannins, while others (like my big piece of Malaysian) will just keep leeching tannins.
Other wood will rot - well, rot faster anyways. Driftwood can be bought in stores for quite a pretty penny (err...nickel? ), or if found boiling it repeatedly is a great way to not only kill the bad stuff but waterlog it.