To run two accounts at the same time you need something to replicate (copy / echo) the keystrokes to both WoWs. If you're using a single PC, you'll need software to do that. If you have multiple PCs, you have a choice of hardware and software solutions, all of which are documented on these forums.

You'll have no trouble finding the basics here:

Software tools forum

Search facility

Wiki

If you're buying Keyclone then Rob (the author) gets a buzz out of talking people through the initial setup by voice and he will be your best bet.

Other than that, enjoy learning what the rest of us also had to learn, and don't hesitate to come back with very specific questions that you can't find answers for in resources linked above.