To my knowledge, there are no VST plugin's for the GT10, which is what you would need for tone adjusting in a DAW. Maybe GuitarRig has some kind of ability to read directly from the GT10, not sure.

There is 3rd party software for the GT10. I'm using it and find it useful. However, I'm also getting rather used to the built in functionality of the on-board screen and menus. It's not that difficult once you get the hang of it.

As far as price? Yes, $500 seems to be the going price. you might be able to find it cheaper if you do an internet search, but, i wouldn't expect much of a difference in price.

Having said that, i've read rumors about the new version of the GT10 coming out next year, so if you wait, there is always that chance that the GT10 will come down in price. I know I'll be looking at the new version and possibly selling my GT10 and getting what ever the next model is... The GT12??? I think they skip odd numbers.