Justin Tadlock
http://justintadlock.com/
GT3 themes
http://www.gt3themes.com/
Free Wp Themes
https://freewpthemes.com/
Digging WordPress
https://digwp.com/
cssigniter
http://www.cssigniter.com/ignite/
CatsWhoCode
http://www.catswhocode.com/blog/
Betterwp
http://betterwp.net/