School me on the Guitalele

I've seen these around for a while, and I am interested in it. I am not good enough on my uke, though, to consider picking up an entirely new instrument. Granted, the top 4 strings are GCEA, but with the addition of the other 2 strings, how do you fret the chords? Are the chords all different, as they are on a guitar? Being that the Guitalele is like a guitar capoed on the 5th fret, would guitar tabs be playable on the guitalele, or is it something new entirely??? Thanks for any info that you can provide. Oh-almost forgot to ask- the only one I have seen online is the Yamaha. Are others out there, or is this, again, something entirely new and Uke makers are not producing them?

Guitaleles can be tuned in different ways. KoAloha and Kanile'a make some high end guitaleles, as well as Mele. Kala had one out for awhile, but it was discontinued.
If you tune it like a guitar with a capo at the 5th fret, you can play your guitar tabs, but they will be in a different key. The chord shapes will be like a guitar, but with different names.
Here is Daniel Ho talking about other tunings for the KoAloha D-VI
http://www.youtube.com/user/ukeKaLori?feature=mhee#p/f/32/3ObKpWPXG9c
–Lori

I like my Yamaha GL1. You can play the Uke chords staright up, if you just avoid the 2 bass strings, just like you would on some guitar chords anyway. The G chord shape on a guitar would be C on the guitalele, if you tune it ADGCEA, as they are intended to be tuned.

I have tuned mine differently, but it is pretty unusual. You can play Low G tabs on the guitalele just fine, and guitar tabs work great too, they just end up sounding higher in pitch.

I have mine tuned re entrant, so it does sound fairly Uke like, but with more resonance at the lower end. I'm using Aquila strings for the 4 high strings, and two guitar strings for the bass notes.

Hope this helps!