Sorry, I was under the impression you were behind a router (not sure *where* I got that impression from though...)
Anyway, once apache is installed, you'll need to find your IP address.
Being a Linux user, I haven't the faintest idea how to do that on Windows, but if you go to my website, you'll be able to find out.
http://www.colinhorne.co.uk/~colin/phpresources/dns.php
That should tell you your IP address. Type it into your browsers location bar, and (if you're running apache) you should get your home page.
If that doesn't work, try going here:
http://127.0.0.1 (this checks apache is working). If that doesn't work, check apache's configeration pages.
Tell me if you're still stuck.
Cheers
--
Please contact me at:
Colin (dot) Horne (at) gmail (dot) com