Google interview is so popular that even MIT dedicates a course to it!
Directly from MIT’s course website,
Learn the tricks. Beat the system.
Ever wanted to work at a company like Google, Apple, or Facebook? There’s just one thing standing in your way: the interview. But there’s no need to fear. We’ve mastered the interview questions and topics, and we want to show you how you can nail every programming question. Whether you’re a beginning programmer or a seasoned expert, this class is for you.
There are a total 5 handouts available for download, with the first few handouts discussing basic data structures and common interview questions with complete solutions. 5 stars and highly recommended!
TopCoder is a very good resource to get started in solving programming problems.