Most people will choose to get a sugar glider from a breeder. It's very important when selecting a breeder, that you try to find somebody that you feel is very conscientious and very committed to sugar glider care. It's important that you be able to call the breeder, talk to them about their experiences, talk to them about the length of time that they've been breeding. And try to find out general information on the care, and the facility in which they breed and raise their sugar gliders. Any breeder should allow you to come and visit their home or environment. They should be willing to let you see where the sugar gliders live. They should also be available to discuss with you diet, and captive care. They should let you know what type of diet works for them. And what they have raised the sugar glider you may take from them on, so you can as well mimic the same type of diet, and know how to feed them properly.
Most breeders should be very involved with sugar glider care. They should have a working knowledge of common health problems. And it should be available to you to talk to them about references, and people who have adopted or purchased sugar gliders in the past. To determine if they have in fact produced healthy babies, if people have been happy with their interactions, and really just the ability to interview them. Find out if they're producing these type of animals for the right reasons. If they care for their sugar gliders very well. And as long as they're willing to share any information they have, and their true desire is to have you purchase one of their gliders, and care for it properly, then I think that's the most important thing you can look for.
It may be difficult to find breeders. Because some of them may be in states where sugar gliders are illegal. Although if you do a quick internet search, you may be able to find some breeders, or some rescues that advertise, and they may have information on how you can connect with a proper breeder. Or somebody close to your area that is going to be raising and selling quality sugar gliders, in a clean, safe environment.