No worries. Try this link, you will have to do some homework though. This search engine is geared for all sorts of hardwares, and if you get specific on model numbers and manufacturers, it provides tons of information, including pdf files for free.
And as a side note, usually if you go to the manufacturers website, they usually have free pdf's on the device of your choosing. You just have to dig around a little.
For example, on the linksys website, you can look up all their routers/gateways and each one has a specific .pdf file on configuration and setup and all sorts of technical data.