I totally get the appeal of wanting to dive into 'Nightwatch' without spending a dime. While I can't directly link to any sites, I can suggest checking out platforms like Project Gutenberg or Open Library—they sometimes have older books available legally.
Another option is to look for author-approved free chapters or promotions on sites like Wattpad or the author's official website. Just be cautious with random sites claiming to offer full books for free; many are sketchy or illegal. Libraries often provide digital copies through apps like Libby or OverDrive, so that’s a safe and ethical route. Supporting authors is important, but I understand budget constraints, so these alternatives might help.