Thanks for your reply.
I'm actually almost 2 hours from Halifax, I just put that in my profile because its the nearest city to me that someone on this site might recognize. There is a Toyota dealer I closer than that, but not one close enough to drop by on my lunch break!
I just had my car jacked up tonight adding a little gear oil (it was down 2 liters!

) (and I am definitely getting some sort of pump next time - it took over an hour to gravity-feed in 2 liters!) ... and looking at the axles I thought that maybe there maybe some sort of seal out near the wheel end of the axle? Maybe that's what he's calling the "outer" seal.
But I can definitely see gear oil seeping out right where the axle goes into the transmission.
It sounds like I should take a long lunch and go to the Toyota parts counter where they probably have a diagram or at least more information than the guy at NAPA.
Thanks again for the thorough reply! For a minute there I thought you were going to dial the number for me and hand me the phone.