I've been hunting for the 'Aku Aku' book too, and let me tell you, it's a bit of a treasure hunt. Thor Heyerdahl's classic isn't always easy to find, but I've had luck with used book sites like AbeBooks and ThriftBooks. They often have vintage copies with that old-book smell I love. For new editions, check out larger retailers like Amazon or Barnes & Noble—they sometimes restock, especially around anthropology-themed holidays.
Local bookstores can surprise you too. I once found a first edition tucked away in a tiny shop in Portland. The owner said it had been sitting there for years waiting for the right nerd (me). If you're into digital, Google Play Books has an e-version, but it lacks the charm of those grainy expedition photos. Pro tip: Set up alerts on eBay for rare prints. I scored a signed copy last year after stalking listings for months. The thrill of the chase is part of the fun with niche books like this.