Theme Forest - The #1 marketplace for premium website templates, including themes for WordPress, Magento, Drupal, Joomla, and more. Create a website, fast.
UpLabs - The best material design, iOS & web resources, every day
ThemeFuse - ThemeFuse is a store that provides high-quality designed WordPress themes to let you stand apart from the crowd.
UI8 - Carefully crafted UI design assets
ThemeGrill - ThemeGrill is an online marketplace that develops and sells WordPress themes and plugins that you can buy to create professional websites for businesses, magazines, and blogs.
Vecteezy - An online marketplace where users can license stock photos, vector graphics, and stock footage directly from artists. Basic features are free but include ads and limitations. Pro subscribers get advanced licensing and a wider selection of content.