Is there an app that does this? There seem to be only apps that save single pages, which safari can do already.
I recommend SiteSucker if you aren't JB'n. If you are, wget has an iOS port.
Read http://www.iphonelife.com/blog/87/offline-web-browsing-and-saving-web-pages
He/she wants to save the entire website. Every page of the site. AFAIK there isn't anything out there that will let you do this.
Well, by providing a rule to both apps that lets for any kind of recursion depth, both are capable of this - after all, wget (and the like) is an industry-standard full site getter for exactly this.
Of course, if non-linked resources need to be saved, no HTTP should be used to access the site but FTP (assuming he knows the password).
Oh! See...one learns something new everyday. Does this work with also sites that are driven by database queries etc? Or is this more for static sites?
Static sites IIRC. Albeit, it could be technically very easy to do a dynamic version too (with a pre-defined dictionary of queries). wget may already support it? DUnno.