If you want those books to play WHFB 4th-5th, they DO HAVE all the spells and magic items completely described and explained in them (I own both, from the time I used to play GW games), and you actually don't need the cards to play, but they do life a lot easier.
Of course, you can make your own cards with the text of the book, but there are lots, and lots, and lots of cards.
Oh, and to be really complete, you need the "Chaos army box" that contained the codex, the spell cards, the chaos gifts, templates, and other chits.
The chaos spells iirc are described within the books, but not the chaos gifts.
But as has been noted, each edition of WHFB has different magic rules and spells, so be totally clear the edition you and your friends are trying to get.
Hope that helps.