My band tried to tour America last year and we got caught up in the whole visa nightmare.
We had to cancel our tour in the end because it was far too expensive and the Americans kept changing the goalposts on the entry forms.
No-one seems to be helping us apart from a campaign by Louder Than War.
They have had meetings with the government but progress is slow.
http://louderthanwar.com/blogs/update-on-american-visa-campaign