The Doakes storyline resolves somewhat differently in the books - I remembered the name and bad times, so I looked it up and was like yeah, that's why I remembered it being bad times. I'm not sure Lila exists as a character in the books (or maybe they're one of the many things I don't remember - there are a lot!). However, I think from what I've seen the first season is an adaption of the first book with a bunch of changes. The later seasons sound like they're a bit more "wow, these books about this serial killer called Dexter are similar but different to the show about the serial killer called Dexter".

-timydamonkey