Grant Kirkhope, the former audio director for Rare responsible for composing the soundtracks of many of their releases, has made the full soundtrack to Banjo Tooie available to download. Technically, it’s pay what you want, but no minimum means it can be had for free if you’re not in an especially generous mood. Also available is the previously released Banjo Kazooie Soundtrack, ensuring you’ll be able to groove to the sweet tunes of classic bear/bird hybrid games no matter where you are.
While the soundtracks were previously available on CD, they’ve long since been out of print and command a high price on eBay. As such, this will be the best option to acquire them legally for the foreseeable future.