The flash has me baffled (question about Canon flash options

As Im sure any good flash would do to any poor soul

Does the EF 500 ST DG have TTL?

If so, how do I get that sucker off camera? I dont see a dedicated Sigma cord anywhere...does the canon one work?

I see the super DG has TTL. Can you use the canon off camera flash cord with that flash and still get TTL?

And whats this about these new "digital flashes" for Canon and Nikon?

Quantaray QDC800 or something like that? Do those have the TTL? How about off camera? can you do that with this guy?

Canon digital cameras do not use TTL or ATTL. They use ETTL or ETTLII and Manual.
If you want ETTL or ETTLII you need an EX series Canon flash, or a flash from another manufacturer that specifically states it works with ETTL or ETTLII.
See the EOS FLASH sticky.
Scott