Quote Originally Posted by alesypalsy View Post
.....and it says only London or Birmingham for these tests?
Where does it say that??
As far as I understand it the candidates may choose whichever test they want from the UKBA approved list. Additionally, many of those test providers have test centres all around the UK.

Just as a couple of quick examples take a Look here for Cambridge English
or take a Look here for IELTS test centres (it says 62 test centres in UK)

There's plenty more tests and providers on the UKBA approved listing.
Just check out by following the links for tests at B1 level

Hope that helps