Maybe Winning Chess Endings by Sierawan? Other suggestions might be Pandolfini's or Silman's endgame course or I think Rueben Fine has a massive endgame text.
Also would be worthwhile for you to tell what you've read so you don't get a bunch of useless suggestions.
http://chessteaching.x10.mx/1001-brilliant-checkmates/
this is a wonderful site to practice and learn many different mates, it just infuses you with the idea of this is what it feels like when i make a good move vs shooting in the dark. i rarely plan every move and just play on feeling, sure i lose and my rating sucks, but i have more fun than being just another loser who studies standards and how to follow rules.
Chess Endgame Training by Rosen or 101 Chess Endgame Tips by Giddins might appeal to you.
http://www.gambitbooks.com/books/Chess_Endgame_Training.html
http://www.gambitbooks.com/books/101_Chess_Endgame_Tips.html
shereshevky's book endgame strategy is the classic on the subject. the other books people have suggested deal mainly with technical endgames.
silmans endgame course. endgames used to be my worst part of the game but now ive become good at them because i read this book. it is a fantastic book.
Thanks for all the responses everyone!
Hello,
I'm a 1300-1500 rated player in search of a good book on endgame strategy; over 25% of the games I lose are lost because I'm unable to come up with a good plan in the endgame. Any suggestions? I'm not looking for a book that teaches only the raw basics (I'm already familiar with things like K vs K+P, the opposition, and all basic checkmates), I want something that talks about semi-advanced things like related squares and formulating a plan.