Laptop was formatted and now the webcam doesnt work. how do I get the webcam to work again?

Without the orginal HDD image, you would need find the specs from when it was bought, find the type of camera locate the driver and go to install hardware and use the wizard. (thats is if it is internal)

For External webcam bought separate from the laptop just install the disk and reload the drivers, or get the model and type go to the manufactuer website and download driver.

You might just be missing the driver (a.k.a software) for the webcam that is on the laptop to make it work. If your webcam is integrated with the laptop you will just need to go to the vendors site and download the necassary driver for it to work.Since you don't have the brand of laptop listed it will be kind of hard to point you to the driver location but most vendors (HP, Dell, Gateway) all have sites that you can get this from.