Be careful with feeding her too much fruit, they get their name from their love of sweet things, but sugar is really bad for them. It has something to do with the calcium: phosphorus ratio in most fruits. Nutritional osteodystrophy (metabolic bone disease, nutritional secondary hyperthyroidism) occurs as a result of an incorrect calcium: phosphorus ratio. This commonly presents as hind leg weakness, and may progress to paralysis.
I got my first glider, Momo, as a rescue as well, she was very antisocial, and just plain mean, so I spoiled her with lots of fruit. I nearly had a heart attack when she could barely move her hind legs. If it wasnt for the vigilance of my fiancee, who figured out what was happening thanks to google, I probably would have lost her. I gave her lots of protein and fluids and she was better in just a few hours. Its terrifying, please dont make the same mistake, it doesnt take long for them to crash.
Veggies are perfectly safe and healthy for them. I'm not sure why someone would suggest otherwise. As far as the monkey pellets go you should see if any pet stores carry sugar glider food. Sunseed Vita sugar glider formula is probably the most common one you will find. My local store has it by the small animal section like ferret and rabbit foods. It comes in a can with a yellow and black label. Its a good balanced diet for them. I used it for a long time before I got the happy glider food. I switched because the breeder I got Max from swore by it, and I like being able to switch flavors.
Heres some info for the happy glider food. I bought mine for a bit cheaper on ebay tho, lol
http://hedgehogsbyvickie.com/sugargliderfood.htm
As for buying a baby your best bet would be a breeder, as opposed to pet shops and idiots at flea markets. When I bought Max I went thru dozens of "breeders" before I found someone I thought was truly a responsible breeder. Not only did she answer all of my many questions, she practically interrogated me on my glider knowledge. Dont be fooled by people that are just trying to make a quick buck, Responsible breeding makes all the difference in the health and happiness of your new joey.