If you have Photoshop CS 3 then there is an option called Photomerge - it provides intelligent and quick panorama from a succession of photos.
How to:
1) Open Photoshop
2) Go to File Menu
3) Go down to Automate
4) Select Photomerge from Submenu
5) It will then ask you to select the files you want to use and the type of panorama you want then hey presto it does it all for you.