Linguists are the only ones who do
use IPA. The reason you're not finding it outside of Vox Latina
is because it really doesn't exist. Vox Latina
is the standard book on how to pronounce Latin, although it's old enough that someone should make a newer standard. If you want to convert that into IPA, that's great, but as you say takes some knowledge of British.
There is always John Traupman's Conversational Latin
, which, although written in American, isn't very technical in pronunciation guides. A combination of the two books may get the job done--I think that's what a lot of us have done.
Ditto with Vox Graeca
. I'm not sure what else is out there to compete with it, though.
As always, with both languages, most of the stuff out there is either referring to the ecclesiastical version of the language, or the hollywood one...