My DD, 27, had been terrified of spiders all her life to the point where she had to slam a book shut if a picture came up, and felt shaky and sweaty afterwards for hours. Live ones, obviously much worse.
It was affecting her life so much she booked a place on the Friendly Spider Course at Regent's Park Zoo. (safe to open - no spider pictures - couple of penguins though 
I didn't honestly believe it would work - she was a fairly extreme case I thought - but late in the afternoon she sent me a pic of her doing something I thought she never, ever would in a million years - and smiling! It meant that much to me I had a little cry looking at it!.
A few weeks later she caught a spider very calmly in the house, using the method she was shown on the course. She can look at pictures of them now without fuss. You have to keep it up though and not let your confidence slide - they were advised on the course to keep up exposure and read books and look at pictures as often as possible.
It wasn't cheap, £135 and you have to get to London obviously, but the thing was, it actually worked, as apparently it does for nearly all participants.
Good luck everyone, it's a horrible fear to have.