New on Archive.org, a good scan of the 1965 hardback of Edgar Rice Burroughs: Master Of Adventure, and with a downloadable PDF.

There is a useful reading guide at the end… “A Princess of Mars [is highly recommended and forms] a single long story that also fills The Gods of Mars (probably the best single volume in the series) and The Warlord of Mars”.

Sounds like the place to start, if you’re not so interested in the Tarzan character. The question then is, where are the best audiobooks? I see all three as Tantor audiobooks (aka Trantor, before copyright trolls forced a name change), read by the excellent Scott Brick circa 2012. Looks good.