They're really, really good. They kind of fit in perfectly because they're all sort of 'tales of Geralt's Life' like the Conan the Barbarian stories, if you ever read them. The first Witcher book is a collection of stories that are in chronological order and they thread together. It's less about his back story and more about his characters... How he met Yennefer, how he met Dandelion etc. Also, there are little stories here and there you realise have been referenced in the games too (Like the CGI trailer for the first Witcher game is basically the first and most classic Witcher tale).
It also just adds a heap more awesome stuff to the Witcher Lore. The next two books are more like novels that are all part of the one big story. It's cool because the whole memory loss thing Geralt had in the games meant that it wasn't seperate canon, the games take place AFTER the books I'm pretty sure.
Also, do yourself a favour and never watch the TV series unless you're REALLY jonesing for more Geralt
Or unless you're drunk and you want a laugh.
