Reboot = you turned it of and back on again.
I'm assuming you mean you formatted and reinstalled Windows?
If that's the case, you'll need the drivers for your wireless car. If Windows didn't install them automatically, they will be on the restore CD that came wtih your computer. If you don't have it anymore, you will need to use a different computer that does have internet access to download the driver.
I found the driver for you, here: http://drivers.softpedia.com/get/NETWORK-CARD/OTHER-NETWORK-CARDS/Dell-Inspiron-1300-B130-Wireless-1470-WLAN-Card-Driver.shtml
You will need to download it and install it on your laptop.
After you do that, you'll need to set up the connection in Windows. The Windows help/troubleshooter can help you with that.
Chances are, there are other other system devices that need drivers also that aren't installed that you don't know about. These devices are equally important and are required for system stability.
I hate to say it, but it sounds like you just enough about computers to be dangerous. I would suggest talking to a friend who maybe knows a little more about computers to make sure all your devices are installed correctly.