You have several options. Two that seem reasonable are (both are things I've done in preparing MOBI files):
1. Download the LIT instead and convert it to MOBI using calibre.
2. Get Sigil and use it to convert the collection of HTML files into a single ePub format ebook. Then you can use calibre to convert the ePub to MOBI.
Other options would be to use an HTML editor to assemble the HTML files into a single file to feed into calibre. I have Dreamweaver for HTML work and I'm reasonably competent with it, but prefer to use Sigil for this type of assembly when the end result is an eBook.
Last edited by dwig; 09-10-2010 at 08:40 PM.
Reason: typos ... @#$@#$% typos ...