Struggling with this a few weeks ago myself (being the greenhorn of servlets that I am), i learned that there are several tasks involved in communicating jsp info to a servlet:
1. Access web data through the request object of a servlet. Strings can be retrieved through get/setParameter, and objects via get/setAttribute(). Add/manipulate them via your session context object when in the servlet doPost method.
2. Don't forget, if you use servlets in your web apps you need to provide a declaration and mapping for them in your web deployment descriptor (your web.xml). This is a twofold task of declaring the servlet (and its class package) in the <servlet> element, and mapping the servlet to a url
pattern (i.e. the initiating jsp) in the <servlet-mapping> element. Your web app container should provide ample info on the details.
3. Include the tag
<form name = "ServletName" action="/ServletName" method = "POST">
and you will be ready to go!
Hope this helps!
Melissa