Here’s a video tutorial from The Reaper Blog about recording doubled guitars on Reaper. Check out the video here. It’s the best way I know of to get a huge guitar sound – even better than recording a single guitar with a stereo mic (or pair of mics).
to summarize the process, simply record your guitar on one track. Then record the SAME part again, on a second track. Once that is done, just pan one of the tracks to the left and the other track to the right. The resulting sound will be a really cool stereo acoustic guitar sound. Try it. You’ll love it:).