YouTube provides transcripts—sort of. They're often missing, especially on old videos, and the formatting leaves much to be desired. The cunningly-named "YouTube Transcripts" website promises superior wordification: "Reading is Faster. Probably won't fail. Easy to Use." (See the Hacker News thread about this site for many useful related tricks and services.)
Getting better YouTube transcripts
Google Images' nightmarish thumbcloud for the search term "YouTube"