Creating multiple indexes or searching multiple sites within one index

[Wolfgang Kierdorf]

Hi there!

I am looking for a way to crawl some sites like:
www.test1.com
www.test2.com
www.test3.com

using one or more indexes and then search a) all (which is no problem 
with one index) or b) some (like only test1.com and test3.com) and show 
a ranked (and combined) search result.

My question is:
is there a way to do (a) and search over multiple indexes
or (b) and search only in some content (like test1.com and test3.com) of 
a single index.

Thx for the help!

BR,
Wolfgang