Well knock me down with a feather, I thought you were using something more powerful.
I bought my first digital camera when they were giving free editing software with the camera, got an early edition of Photoshop Elements, but when my computer expired on me last April, the PS software went with it as I managed to loose the licence no. Now I use GIMP free editing software downloaded straight of the internet.
Loads of free tutorials out there, great for editing maps as well as photos.