Images that are protected under GNU license cannot be used in a commercial product right? There are some open source projects that have some icons that I like and would like to use in a commercial product. Im been quite lazy for not reading the license in full, but I am confident its forbidden. Where would be a good place to find general icons to use for a back end CMS control panel. Like icons that display things like: Users, Configs, Tools, you know the general nice icons..
Paying someone a little chunk of change to do it would save you a lot of time and money in the long run especially if you can't find any right off - there probably isn't any out there.
The GNU/GPL doesnot prohibit you from making money from it. you can sell/distribute gpl protected item freely. The only restriction,as far as i know, is you cannot claim that protected item to be your. And anything produced from GPL protected item are under GPL ,too in your case ,I agreed/think that it is prohibited. another suggestion is asking the free software foundation directly about your case