with Javtalk down, which was one of the best sites around for japanese AV torrents, there is a new one from the more infamous Banana Boy who posts a great number of newly released AV, but you need to register:
http://javbb.com/forum/viewforum.php?f=2
another good site I refer to for direct downloads:
http://pornrapidshare.com/video/free_porn_movies/asian/
for the Rapidshare downloads, i don't buy, i only use the free, the trick is to download one file at a time.
there are certain busy times during the day (north america), but at night in north america, there is no restriction usually for downloads one at a time!