
Hi
I was looking into this a while back.
If you find the official guide dogs for the blind website, there are links to jobs on there, though there arent many centres, however last time i looked they had a fair few jobs going, all with fairly good pay, and opportunitys to be promoted!
Earlier in the year, the CPI (now Canine Partners) were looking for assistant dog trainers, though a driving licence is necessary, they are very good, will take down your details, adn email you when they have a job coming up (unlike some places who say they will do that, but dont!).
I dont know about hearing dogs. Hope taht helps you.
Em