I took the Backstage Safari Tour last fall and it is the best tours I have done to date at WDW. It is $65. There are discounts if you are a DVC member, AP holder, Disney Visa, or CM (make sure to ask when you book the tour (407-WDW-TOUR)).
We broke off into two groups backstage and used some vans to move around backstage in. If Paul is one of your tourguides I highly suggest getting in his van as he was an amazing tourguide. I believe he is a retired school teacher in MI if my memory serves me right and he explained things so well and had so much to share with us.
We got to see a lot of neat backstage stuff: Elephant Barn, White Rhino Barn (we did get to pet one as well), vet office, area where the food is prepped, the aviary, we had a break in there too to watch a film and we got to meet an owl. Also it was awesome to ride the KJS afterwards with Paul taking the microphone and telling us all of the tricks and hidden things in the safari.