Phone screen didn't really consist of traditional programming problems, but was asked a lot of questions about my experience.
One HR screen, very typical questions; easy.
On site interview consists of 5 one-one interviews. 3 interviews before lunch were a mix of 1. going over my resume, and then 2. 1/2 - 2 hours programming / design question.
There's no way I could have studied for the questions they asked, but a good understanding algorithms, design patterns, and an expertise in the language of your choice (eg. C# or C++) will do you fine. Relax, be yourself, and get a nights sleep.