Apple's iTunes remote is a nifty app for iOS, and I used it quite a back back when I had more iOS devices. With my move to Android however, Winamp has taken the place of iTunes as my computer side media player, since I no longer need iTunes to sync music. After a bit of looking around and going down a wrong path with an abandoned app, I found aWARemote.
The app works like every other remote control app in the history of mankind: install a server from the app's website, hook up to it using the app. This all worked flawlessly for me, and I had it up and running in seconds. It then lets you download a database of your music files as well as the album art, so you can browse files and see full track info rather than just controlling play/pause/next/prev. This is what makes it better than e.g. Unified Remote for this particular task, as you can actually control the full aspect of browsing your media library from this app.
The app seems to be working just fine, with the exception of .m4a/aac album art, which is the most typical problem in the history of music playback. The other, abandoned app I tried had a tendency to crash Winamp, which this haven't done yet, thankfully. Between it actually working, getting updates, and the UI being quite nice, it's a great app if you like listening to music from your PC but still have control over it from a handheld unit.