new blog looks great, but need help w/errors

[rtacoma]

my new blog at Laser Eye Surgery Blog is pretty much done ... still a few more changes to make ... but am concerned with errors i'm getting when navigating the site...

here is what I'm getting...

error when clicking rss feed icons, categories, recent articles and leave a comment...

Not Found
The requested URL /index.php was not found on this server.

Additionally, a 404 Not Found error was encountered while trying to use an ErrorDocument to handle the request.

index.php does exist ... so I'm stymied as to why I'm getting these errors

any help would be appreciated ...

thanks

Ralph