Ive just realised what a MASSIVE help recorded interviews are!
While researching designers such as Amy Westcott, Colleen Atwood and Penny rose (and loads more) i found these interviews and they tell you what problems they had to deal with and stuff like that!
REALLLLLY HELPFUL.

Colleen Atwood - Alice in Wonderland
Amy Westcott - Black Swan
Penny Rose - Prince of Persia
Alexandra Byrne - Elizabeth the Golden Age