We met at the Mendip Meet, I've not chimed in earlier, because my info relates back to 2005, when I travelled from New York to South America.
When I applied for a B2 tourist visa it was about 6 weeks waiting time for the appointment in London (I understand you can choose Belfast),
During the wait and after you have lodged electronicly all your details you have to credit theiir bank with £60 (2005)
When attending appointment (do not be late!!!) was linned up in the street (lucky it was not raining) and sent thro' in waves of abouit thirty applicants, following screening entered a large hall where there must have been 200 people plus waiting, where you wait to be called to first interview, this is followed by a second interview after a wait, from which, if you are successfull, you will be advised to pay courier fee (£39 - I think) for return of passport with a 10 year B2 Visa.
Hope this helps some, although as stated this was more than five years ago.......Best wishes Alec.
I wanna go back.