HTTrack is a free utility that allows you to download a World Wide Web site from the Internet to a local directory, building recursively all directories, getting HTML, images, and other files from the server to your computer. You can get more details and download the tool from http://www.httrack.com/
This page explains the steps you need to perform using HTTrack to download a website or existing wiki into a local directory, so it can be given as an input to import into SamePage.
When you run the tool the first screen will prompt you for “New project name” and base path. The base path is a path in your local machine where the files will be exported to.
Next you need to provide the base URL for the tool to start the export.
Click on “set options” to set the Maximum external depth parameter on “Limits” tab to “0”. Also, set the Local structure type parameter on “Build” tab to “site structure without www.domain.com/” as show in the screen shot below
Click next and it will start the export. Wait till you get the success message and verify the imported pages by clicking the “Browse mirrored site” link on the finish page.