I'd like to offer my help here. As well as doing my own leather design work, I also do Digital logo design.
I have used Pixie, Gimp and several other prorams. I found some of them far to complicated; i.e GIMP
I have used this program http://www.irfanview.com/ for some years now. I use the basic program, together with my printer/scanner.
If your a bit computer savy, this will work much simpler than GIMP.
Of course, resizing is a bit of a pain but it is specfied on many websites,
You can do this very quickly without leaving said website.
NOTE: IRANVIEW :the resizing tends to keep the original quallity) Here are a few things I use it for everyday.
Cropping and Resizing Photograghs
Resizing patterns. pictures and line drawings
Grayscaling
Creating line drawings from photographs
Hope this helps!