Here's another site that I have used and have been happy with. Nice thing about these guys is that you can buy a paper copy of the manual. They focus mainly on electronic products.
I first found them when I bought a new camera which had the user manual on disk only - tough to use when you're site seeing. I could have printed the manual, or taken the disk to Staples for printing. I concluded that Manuals Ink was the best, lowest cost option.