I agree with Doggfather.Discus are not for everybody,not only the time and dedication,but the space and proper knowledge of how to maintain a fish tank.
Having said that.....if you have the knowledge,dedication,time and space just read about them,especially on websites from your area,I imagine Australia(?).
A few things I will like to add.They are not impossible to keep,is just that they are delicate and any major change in parameters may harm them.
--Since this is the first time buying them,remember to get at least two.They feel better in small groups,it will give them a sense of security.
--Try not to buy wild ones.These are the most difficult to keep.Not only they won't eat flakes and give you headaches,but they tend to be more shy,making everything more difficult for you.
--When ready to buy,go with somebody else,even if this other person doesn't know much about discus.Why? 'cause many times their beauty will blind you.
Things that you want to look for....
Do not but if you see some sort of skin illness.Trust me,don't do it,even if you thing you can cure it.Stay away from blurry eyes,and speaking of eyes......Make sure that the size of the eye correspond to the size of the body itself.Fish that haven't grown properly for whatever reason tend to have larger eyes in comparison to their body size.
--Observe very carefully.If you see a discus being in charge,that's probably the one you want.Just by staring long enough,you will find the other contender to the throne and the ones that get along with the "alpha"(dominant).
--Ask someone to feed them.Why you ask? 'cause,discus are well known to be very picky about the food they eat.This is another reason why wild ones are not good for a beginner.If you see them eating flakes,you are home free;Ask the person if they're used to eat frozen or live food,you may also want to concider make their own food from scratch,you'll find many recipies from any website.
These are only a few things,but you are on the right track,keep asking questions before you decide to make the decision.
Good luck.
