I have never been more convincing than what I did an hour ago that a licensed Photoshop CS4 could cost you more than $600. Fortunately, I do not have to spend those $$ on these licensed Adobes.
I have tried stitched photos for a couple of times, but it was very time-consuming and I have always had problem with blending exposures as each photo got slightly different one. With Automate Photomerge, it works a like magic. What you should do is just wait a minute or two. It will do all the dirty works for you flawlessly.