A tribute to the original ToTheBestOf.
It follows a similar flow when you come across a new music band. First, it checks their top ten in last.fm, then searches for those songs on Youtube.
The original TTBO used Grooveshark, a long-dead music streaming service. In today's world, there are alternative streaming options with minimal costs.
Spotify is one of those services, and it's big. Citing Wikipedia: "As of June 2016, it has 100 million monthly active users, and as of March 2017, it has 50 million paying subscribers." As much as Spotify has to offer, it's library doesn't cover all artists.