Hi, Stu:

No, I didn't mean to say that one should learn piano before learning guitar. I understand your point about my own visualization of notes, but again I disagree with your statement that it "doesn't help to learn anything about the piano" in order to play guitar. I'm certainly not saying that one needs to learn how to play chords on a piano before learning to play the same chords on guitar. I am saying that the piano keyboard can be a useful tool for beginning guitarists when it comes to visualizing BASIC MUSIC THEORY (and not that it absolutely is or is not). Okay???

Anyway, I found a couple of guitar-fingering reference pages, on the same site as the piano-keyboard page, with many of the same features. Check out the chord fingering, listen to the chord as it's played, look at scales in different keys, do it all in different tunings, etc. Here are the pages:

Guitar Room (Easy)

Guitar Room (Advanced)