did you get software with your Canon jean? There is a programme in it called photostitch which does this easily.
I don't have elements, I've got the full p/shop caboodle but this is how I would do it in P/shop...
and this will take a while....so get your gin ready
This method doesn't go into blending and fixing the join and flattening layers too much - I can give you that info if you want but if the pics are pretty well lined up you could get away with using your healing and cloning tools on the join. Make sure you have all 3 images open in P/shop before you start.
1. enlarge your canvas
open the first shot, go windows then layers. doubleclick background layer and click ok to turn it into a normal layer.
go to image/resize/canvas size (make sure 'relative' is clicked). enter Width 100%, Height 10%. Click the middle right anchor box and click ok.
2. straighten image
ctrl T (enters Free Transform mode and bring up a bounding box around the pic) Drag your mouse outside the shot to move it into the right straight position and use the arrow keys to straighten move it to the right place. Hit enter to apply. Press Layer/flatten image to turn layer 0 into the background layer. open up the 2nd image and go to select/all (ctrl A) then edit/copy (ctrl C). Close image.
3 Align the second shot
Have your main image active, go to edit/paste (ctrl V) to bring in your 2nd image. Now hit 5 on the keyboard to reduce opacity to 50%. Ctrl T and drag 2nd pic to roughly into place. as before ; Drag your mouse outside the shot to move it into the right straight position and use the arrow keys to straighten move it to the right place. Try and match up in the middle of the overlapping area. Hit enter
Hit the Zero key to bring opacity back to 100 percent.
Press Layer/flatten image to turn layer 0 into the background layer. open up the 2nd image and go to select/all (ctrl A) then edit/copy (ctrl C). Close image.
repeat 3 for 3rd shot.
4. Crop the shot
zoom out of the image and select crop tool. Drag out a crop marquee then drag over image to shape/size.
Flatten image (layers/flatten image) and apply all your usual adjustments. If you're still having trouble with the joins use the Clone and Healing Brush tools.