I would heartily recommend Nigel Davies' repertoire offering. It's well-thought out and the information is well organized.
For the price, you get a complete black repertoire of the same vein too.
http://tigerchess.com/courses/building-an-opening-repertoire/
Hello. Could you please recommend me a book for the Colle System? I would like a reliable one and the one that will be my first position on this specific opening. Additionally, I'd like it to be focused more on ideas (understanding) than very specific and numerous lines (memorizing).