I put most of my anger in a journal. In fact, I affectionately called it my "Book of Anger," and it was filled with vile language and lots of CAPS and !!!!!!!!!!! I still have it, too. Sometimes I look back through it and get amazed at the amount of anger I had.
The other thing I would do was go for a drive, put on some really loud music, and scream out everything that I was angry about. (Janis Joplin is good for this, LOL)
Therapy was helpful, too, but the journal was the biggest help because I could go there whenever the anger came.
L