as mark said before , you can deal with sharepoint by using ECMA-Scripts
(if you want to get data in client side)
if you are , try to look at this link :
http://www.learningsharepoint.com/2011/05/16/get-all-list-items-using-ecmascript-sharepoint-2010/[
^]
or you can get data in server side by object model
using Classes like : SPContext , SPSite, SPWeb ,SPList ,SPListItemCollection
,SPListItem and so on.
try one of these solution , and it will be done succefully.
if you want to share your task in a little bit of details , i can help
you get the best solution.
do not hesitate to ask a question , do not worry.