Each computer on the network must have its own IP address. A network could be defined as your home network, or the internet, your work intranet, etc...
On your 2 wireless laptops, if they are connecting to a wireless access point / router things normally work like this:
Wireless access point / router has a REAL internet IP address: 188.8.131.52 (for example)
Then, each latop gets assigned a internal IP address by the router.
Laptop 1: 192.168.1.1
Laptop 2: 192.168.1.2
If you are browsing the web, your IP address will be the routers IP (184.108.40.206), but if you are connecting between the 2 laptops, you reference them via their internal network IP address (192.168.1.?)
To find out your local ip adddress, just open up a cmd prompt and type "ipconfig"
To find out your routers IP address, you can go to many websites that will tell you what it is (whatismyipaddress.com is one that I found in google)
Also, most users have a dynamic IP address so it can and will change.