Original X-Men comics?

Does anyone know where I can find the original X-Men comics? My bro has a ton of X-Men comics but not what I want to read. I mean, like, number 1-???. Also, usually books get published with some of an entire series together. For example: Thed Chronicles Of Narnia. All the books were put in one big... Book? I was wondering if any of the original X-Men comics had been done like that. It would make purchasing them a lot easier. Sorry, for my ignorance. I'm used to novels. Just got into the whole comic book-thing.