I'm a mac-o-phile, and I don't know of anything either. Doesn't mean there's nothing out there, but I haven't run across it yet.
There are a couple of excel spreadsheets you may or may not find useful:
Xlbox.xls
Xlbaffle.xls
Sealed Box Calcs.
load.xls (for tube current/loading IIRC)
I downloaded all these off the web- I did not write them, I merely benefit from other's generosity. If you can't find them, email me and I'll send them to you.My theater 4 pi's are sounding great Wayne! I rarely post, cause there's not too much to say about them besides that they are the best sounding speakers I've ever had.
cheers,
Jason