Podfic has been around for almost as long as fanfiction itself. Since the early days of zines, people have been recording and sharing podfic, though it hasn't always been known as such. Back then it would be on cassette tapes and later CDs and only shared at conventions and in select fan groups. Today, most podfic now is hosted on the internet and the primary place to find it is AO3, but it is found all over including on SoundCloud, The Internet Archive, and YouTube.
Click in the links below or scroll down to learn more about what each of these resources has to offer.
The Fanlore entry on podfic
The Fanlore entry on Audio Recording.
A glossary of terms
A basic and very comprehensive guide by Azdaema.
"A bunch of tips, tutos and links (oh gosh so many links) for aspiring and accomplished podficcers alike" by Annapods.
Literarion describes their own podfic creation process.
A step-by-step guide by Dragongirl.
A masterpost of all the podfic creation guides by fishandchipsandvinegar.
A simple, step--by-step breakdown of the podficcing process by GoLB.
A step-by-step slides presentation on how Ravin makes podfics.
Repodding is when a second podfic is made of a fanfic that already has a podfic
The Podfic Repod Challenge
A podcast episode about repodding
A blog post about why repodding is a good thing
The Fanlore article on repodding