Add two bindings to your website, one for local access and another for LAN access like so:
Open IIS and select your local website (that you want to access from your local network) from the left panel:
Connections > server (user-pc) > sites > local site
Open Bindings on the right panel under Actions tab add these bindings:
Local:
Type: http Ip Address: All Unassigned Port: 80 Host name: samplesite.local
LAN:
Type: http Ip Address: <Network address of the hosting machine ex. 192.168.0.10> Port: 80 Host name: <Leave it blank>
Voila, you should be able to access the website from any machine on your local network by using the host's LAN IP address (192.168.0.10 in the above example) as the site url.
NOTE:
if you want to access the website from LAN using a host name (like samplesite.local) instead of an ip address, add the host name to the hosts file on the local network machine (The hosts file can be found in "C:\Windows\System32\drivers\etc\hosts" in windows, or "/etc/hosts" in ubuntu):
192.168.0.10 samplesite.local