||Apache Web Serving with Jaguar, Part 2|
|Subject:||Sites directory not named in default httpd.conf|
gives you a 404 (can't find), check your httpd.conf file for this little chunk setting the directory name appended to a ~username/ browser request (mine was like this by default)...
...then (if your web pages are in the OS X-supplied directory called 'Sites') either alter 'public_html' above to read 'Sites' or change your 'Sites' directory to 'public_html'.
- Dave Everitt