I'd argue that Inkscape is as good as the above product.
If you don't like Gimp (it's the bigger and best of the free image editors) the buy Adobe Photoshop Elements. Elements can do almost everything PS can, well at least in terms of what a photographer needs.
But again the software hardly matters. The difference between a commercial artist and a fine artist is that the commercial guy is TOLD what style to work in and what colts to use and where to leave blank space for text and may have to work in a genre he does not really like. In other words you work for a paying customer or boss. So what they look for is a person with very wide skills who can do anything.
Session musicians are that way too. They just do whatever the producer wants so if he needs the work he has "a, I can do that.." So the trick is to be able to say "I can do that."
ok one more tip on cheap/free software: Wacom tablets. You are going to need a Wacom tablet and some version come bundled with free software. Sometimes the software is worth the cost of the product. I got PS (full version) that way a long time ago.
For me, Inkscape is a non starter because it won't open my Illustrator files!