Word Press Query

I have 4 blogs now with Word Press Mu. I want to be able to query each blog from the site index page and have different loops after each one to display some entries from each blog (so 4 query calls and 4 loops).

I’m having trouble finding how to do the query part before each loop. This is done automatically when I’m working with a page for a particular blog, but for the site index page I’ll have to do it manually 4 times.

I think I’m supposed to use wp_query() somehow, but I’m not sure. Does anyone know how to load the entry data from a particular blog before the loops?

Thanks