how to save web pages locally

hi all.

there is a situation: i want to make,so to say, a catalog of production.

after first launching an app, all categories of production will download as "some data base" from some web page and shown at table view

if a user wants to see the detail information, the data from another web page downloads to "some place at iphone" and after shown to user in a webview

are there some ideas how to do that and with what instruments?

sorry for english and maybe no understanding some fundamental and simple things, but it's nesessary for me to make this in my project.