Heh... Try Bing/Googling "Windows 10 Themes" for starters. Lots of "skins" there... As well, the OS is so flexible from the standpoint of the GUI that no "apps" are required to customize the way it looks.
Whats wrong cant I ask for what people who would know the best, tweak apps, Customization apps, Fonts and ect??? I have rainmeter but don know how to use it, only the basics. Any help there? Links to some good guides would be nice.