Hi Sam
We got married in Studland a few years ago and used local people/companies for most of it. Will ask Jess to dig out the details. It's a bit like boats in that they hear the word 'wedding' and add a 0 to the price.
Suit hire we used Austin Reed, they did a groom goes free when you hire for the rest of the wedding party - as they've just gone bust maybe they'll be selling off their hire stock?
Invitations we made our own, sourced the bits from Cards and Pockets in the USA, really efficient and much cheaper than over here - http://www.cardsandpockets.com/
Photographer was a favour from a close friend so can't help you with that, but the cake was made by someone local so will find out for you.
Oli
EDIT:
Cake - Jenny Budzinski - http://miss-ingredient.co.uk/- was fantastic
Hair - Tracy - http://brideshair.co.uk/- obviously I didn't get involved with this but Jess and the girls loved her and would highly recommend.