Yes best is if you buy a book (not such 21 days or for dummys crap like mullah advises LOL
anyways u should get a big fat book which also contains a refernce, also read the foreword of the book or the part where it says "is this the right book for me" or "this book is for ppls etc". if u think that what the author says is that what u want or are buy it.
also u should bring a lot of time for concentrated reading and understanding (u should knowe a bit how ur pcs works), means u need know about the hexadecimal, decimal, binary system. make sure your book describes the the c++ language in the ansi-c/c++ standard if u want to learn this language really in all his parts.