You will first need to get a suitable camera for your photo.
I would suggest a higher end model like a DSLR (I can't recommend one sorry) but if you are pressed for money or just don't want to spend so much I would just select a good camera 4 megapixels or more for example (the one i used is 4.1 megapixels).
You will then want to choose a topic and if you will want to meld two pictures together. For my first picture I chose to use fruit and a wine bottle (painted by my Grandpa). I thought it would be good to replace the dull back wall of my cottage with a view of the lake outside.
If you have chosen to go further than just taking the picture and leaving it as is you will need Photoshop Elements 7. This is what I used to do all of the editing and merging of photos but you dont need to do these things.