http://opengameart.org/blog
http://www.gas13.ru/v3/tutorials/sywtbapa_almighty_grass_tile.php
http://pixel-zone.rpgdx.net/shtml/tutmini-rocks.shtml
http://www.pixeljoint.com/pixels/tutorials.asp
http://tutorialblog.org/pixel-art-tutorials/
http://www.derekyu.com/?page_id=218