Help with Converting Static Sites to WP

I have some old static content sites that I want to switch over to WordPress. I have 100+ pages on each site and was looking for an easy (?) way to copy the content across.

The existing sites have the folder structure: mysite.com/keywordfolder/index.php which fits in nicely with the way WP page structure works.

I'm not really looking forward to the task of copying across thousands of pages manually. If there is a plugin or tool that could help my situation then it would be awesome.

cheers