Its not uncommon for laptop keyboards to die. However this site has many wonderful tips and suggestions for repair and replacement
The best source for replacement keyboards is EBAY I get many laptop parts from there and have never had a single issue with the component suppliers. I would stress that you should get a NEW one as opposed to a second hand one. The price difference is marginal at best but at least you know you are getting one that works.
Also double check you get the correct keyboard for your country.
As you may have already seen they are pretty simple to do and are quite often cheaper than a regular keyboard.
You could also plug a regular keyboard into the laptop too to get you going again until you fix the existing one.
Any USB keyboard will work just fine in fact my girlfriend prefers to use her laptop with a full size keyboard.