Tactics and Planning.

I have been following conventional wisdom on spending my training time on tactics problems.  It seems to be working.  I have been on a winning streak lately with my online games, often being able to win a small material advantage and take that advantage into a winning endgame. 

I certainly plan to keep up on this, but I am also hoping to take this to the next level.  I would like to start studying something on taking a tactical aggressivenessto a planning level.  By that I mean I would like to be not just looking at a "find the best move" puzzle, but perhaps some material on how to take those tactics and incorporate them into a larger plan, such as attacking a castled king, advancing in the center, queen side minority attack, etc.

Can anyone reccomend a book or series of books that might be good for the improving player on these topics?

Shameless bump to keep this on the front page.

I believe I've heard good things about this book: Imagination in Chess: How to Think Creatively and Avoid Foolish Mistakes

I don't actually have the book, so keep that in mind.