bill - 6:13 am on Sep 13, 2004 (gmt 0)
I have not submitted any of my recent Chinese language sites to a search engine. If you have links to your sites then Google and the rest will find them on their own. Submitting isn't a necessity, and some people will advise against it.
Add Yisou to that list and you'll have all the worthwhile ones for mainland China. Maybe someone who knows the TW and HK markets could fill you in on the gaps there.
Also, I have listed below a few other popular Chinese search engines. Are there any other major ones that I've missed?