Okay, the challenge has been made: explain how Ryouga knew where 
Ranma would be staying and where he'd be going to school. To that end.
..

(Scene: A grocer stall in a small village on the outskirts of the 
Qinghai province, China. A week after Joketsuzoku.)

(Ranma and Genma are talking as they browse through the wares.)

Ranma: So, where we headin' next Pop?

Genma: Well, since we need to get back to Japan in a hurry, and in 
light of our...new situation, we're going to be staying with my old 
training partner Tendou Soun for a while, in Nerima. I already sent 
him a postcard. (pushes up his glasses) And while we're there, you'll 
be attending the local high school, Fuurinkan.

Ranma: School, bleah.

Genma: Listen, boy! A martial artist's mind is just as important as 
his body! Never forget that!

Ranma: Yeah, whatever. Guess it won't be too bad. 

(They leave. Neither has noticed a small shadow hiding in the alley...
)

Ryouga: (pig form) (thought) So...Fuurinkan-koukou...Saotome Ranma, 
I'll find your new schol, and when I do, I'll beat your cursed hide 
to paste!

(Just then, an old woman with a sharp butcher knife comes into view.
)

Woman: Ah, a piglet! Perfect for some sweet and sour pork...

Ryouga: (terrified) BUKII!!!!!!!! (He takes off, with the woman in 
hot pursuit.)

Ryouga: (thought) CUUUUUURRRRSSSSSE YOOOOOOOOU 
SAOOOOOTOOOOOMEEEEEEE!!!!1

____
Saraba da!
-The Eternal Lost Lurker
http://pages.prodigy.com/RMorrison