You're probably set up to receive your IP information automatically from a DHCP server.
If you can get this information you can enter it in manually and set it all statically so that Windows doesn't have to request this information each time it reboots.
You will need your IP address, Subnet Mask, Gateway address, and at least one DNS server address. Most ISPs have two, a primary and secondary. You can email them for this information and they should give it to you. Otherwise, you can go to the command prompt and type in NSLOOKUP. It will have a default server name and IP address. The IP adress it gives you is the address of your primary DNS server (more than likely), so you can use that one and find the other out later.