I ended up breaking a keyboard key on my laptop and was rather non-plussed to see that full replacement keyboards were $30+.
Two websites, replacementlaptopkeys.com and laptopkey.com, offer individual replacement keys. They're essentially pure margin at $5 / key (excluding shipping), but they do offer step-by-step instructions for how to order the proper key that fits your keyboard and heck it's a lot better than paying the full amount for the full replacement keyboard.
I was a bit leery that there weren't many reviews of the websites, but NYTimes mentioned both of them in a blog post, so that gave a bit of comfort. I ended up ordering from
replacementlaptopkeys.com, due to the slightly cheaper shipping and just received my key.
Shipping took about 5 days from the day of my purchase (shipping from California to Atlanta). The key came in a standard letter envelope, scotch-taped and packed inside of a paper towel, making me suspect this is a side-home business that is maximizing their margins. But hey, the important thing is that I received the key and it is working fine now.