comments:
1. if u r working at INTRANET(many computer connected to each other ) you can get your ip address by 'ipconfig' command from dos prompt at windows or 'ifconfig' terminal command at linux
2. after getting your the internally IP address, each computer in your lan can access your machinehttp://your_ip_address orhttp://your_computer_name
but check at your httpd.conf (found at APACHE_HOME/conf/) therte is line containing Listen 80 and not commented.
3. to access your machine from outside your lan .. you have to get your INTERNET IP address (your lan computers will never can use this IP)
4. as Grizzlydk said (thank's Grizzlydk ) f your lan have router .. you MUST make redirection (using NAPT) for your url
check these 4 points and tell me what you need ...