https://wordpress.org/themes/

http://themeforest.net/category/wordpress

http://www.elegantthemes.com/

http://www.rockettheme.com/wordpress/themes

http://www.webmasteo.com/themes/wordpress/

http://www.creativebloq.com/web-design/free-wordpress-themes-712429

http://wp-infinity.com/theme-wordpress-premium/