Do public Web search sites have APIs?

Hi,

We are studying Web search engines. As you all know, when you send a
request, they answer with a Web page listing the result. The question is:

Do anyone knows if  search sites like Yahoo, lycos, excite, hotbot, etc..
have an API that returns the result as a list of sites or is it strictly a
result packaged as a HTML page? So, basically is there an other way to
obtain the resulting meta-information through other ways than parsing the
resulting HTML page? 

If anyone knows where to get information about their query language (if
they have one) and ways to specify the desired result, we would greatly
appreciate your help. The goal is that we try to fing if these search site
do more than just returning a HTML page, can they return meta information
that can be further processed? (not just readable information that has to
be processed to extract the meta information)

Didier PH Martin
martind@netfolder.com