I recently added driftwood, following and modifying advice found here on PC. (I'm a newbie)
Boiling the driftwood is a way to help sterilize (assuming it fits in a large pan). Folks also suggest running it thru dishwasher with no soap a few times after scrubbing it down.
I chose to boil it, then let it sit 3 - 6 hours (in this 'psuedo-heavy water'), change darkened water; boil again, let sit... etc. I did this for a three or four days; -- reminding me of quieter days when I let the teapot humidify the house...
Even tho I live on a local creek I felt more secure buying drift wood at LFS (I think it is already a little processed/cleaned); mopani and grapewood tho you can read here that local native wood is a good and less expensive option (preferably not pine and a few other 'caveats').
Alot of tannins were released in the 'boiling and sitting' procedure. The advice was to let it sit in bucket a few weeks to a few months. I was hoping the boiling and sitting process would hurry to stabilize the tannin 'release'.
I ended up using the grapewood after about a week (it still wanted to float), but kept the mopani in my heated hospital tank for a few weeks to allow it to continue to 'cure'.
BTW, be sure to check out Shane's World articles (by various folks). I also used the Search function here on Planetcatfish whenever I had a question... e.g. could type in 'driftwood'.
Hope this gives you more choices. Good luck!