The archive is controled by the archive/index.php file...
Depending on where you want your html placed, you might have to use
echo statements. There is a chunk of the body that is outside of PHP tags IIRC.
The file structure is pretty simple, the 3 main sections are:
- Main Page
- Forums
- Threads
If you take the time to read over the file it is pretty self explanatory, if you don't understand PHP at all, then do yourself a favor and spend some time reading at
www.php.net to learn some basics.