These brushes are made for GIMP. You are allowed to convert them for Photoshop, or any other graphics software but please credit the team at Tech Net Blogger (http://www.technetblogger.com) as their original author. A link to the site is a fine way to give credit.
These brushes are free to use in personal and commercial projects. Use them as you please, and if possible, link back to Tech Net Blogger (http://www.technetblogger.com). A link is not required but it will be greatly appreciated.
The only limitation in use is that you can't sell them, or repackage them and claim as your own. Aside from that, you are free to use them any way you deem fit.