I can't read Japanese myself, but from looking over this site with the help of Google Translate's (very garbled) results, it has a lot of information on detailed game mechanics and strategy, much of which doesn't seem to have ever made it over to the English Touhou wiki or any other English Touhou reference:
東方 Project 攻略 WikiI've just added a link to it on the English Touhou wiki's links page, but I figured I'd bring it to people's attention here as well. While I'm not a real player myself (I just like watching high score replays), I figure that there must be some English-speaking Touhou players who would appreciate this info, if potential translators could help out.