I am going to teach you how to blend in Paint Shop Pro. The method I'm showing you is how I blend, although there are other ways I find this one the easiest and more efficient.

First, collect 3 images (you can use more once you get used to blending).
First of all make a new image about 600x400.
Copy and paste one of the photos onto the new image (click ctrl L) And move to the left side using this tool:

Copy your next photo and paste onto the same image as the last using the move tool again. Position so the image is overlapping the other one. Select the eraser tool:  Use the round brush on an opacity of about 2. Blend the image using different opacities if needed until your satisfied.

For the last image just repeat the previous steps. Once you're done add some decorative brushes, save and you're done! :)