You can plug your Inc into your PC via the micro usb cable. Upon connecting the device, your PC should automatically detect your microSD card and, depending on Windows version, give you options on how you want to view the storage (one of them is "open to view contents" or something like that).
Then you can drag and drop your files onto the SD card. I suggest making a directory first so you can keep your files organized. Also, I suggest you get a file manager, like Astro File Manager (search Astro on the market). Basically the file manager will allow you to look into your SD card on your phone.
There's an app called Quickoffice (i can't remember if this comes stock on Inc or not) that will allow the viewing of word documents and other typed documents, however it is not able to edit files. You'll need to check the Market for something that could handle file modifications.
Edit: there are a few apps that act as Office suites, however they are paid apps. If anyone knows of a freebee available, I'd be interested too.