A little question... Watch
My laptop is a Dell Inspiron 6000... Thanks again!
Best suggestions I can make are:
1) try eBay for a damaged laptop or just keyboard from the same model - often the keys just pop off and you can pop it back onto your machine.
2) try Dell for a quote (they probably won't sell you a replacement keyboard directly but will want to take it in for repair) - you might be able to convince them it's a warranty issue if your machine is fairly recent (like the key just popped off, can't get it back on, etc. but not very plausible if you don't have the loose key...)
Unfortunately laptop keyboards are not just expensive but also can be a complete ***** to fit. I had Apple replace the keyboard in my Powerbook and it cost me £50 - I thought that was expensive!