Trooper Walsh is the man known for the blue line. TW and AZ paired up to make this color appear. They ended up with Mister Blue, there is also Carolina Blue. These are said to be the starting points for the blue line. Getting any descendant from one of these is going to be pricey. For some amazing blue snakes please check out which host MY personal favorite, Skyy.

You can take you chances (and they really aren't that bad) on buying a blue line baby. It might look just like a super nice Sorong local, but being from the blue line and linage proving to that makes it a small gold mine.
A true blue snake is one who completes it's ontogenic color change into blue. Hormonal blue has been discussed, but to me it's irrelevant. If it is genetic, it only appears in females who have breed. If she turns blue,and stays blue, after her first clutch and breeds the next season, it will not make your chances of getting blue babies any more likely. However, it does make for a nicer animal to look at.

If I have been keeping up with everything correctly (and at the breeding part, it's more in Brandon's court) Blue line is either from a descendant of Mr. Blue or Carolina Blue. A super blue line is when you breed a descendant of each together. There are defiantly many other blue lines out there, but these are the main two. Kirk Mills has a snake called "Arctic Blue" which from my understanding is a WC import from Indonesia. He got 2 clutches from him this year, but I don't think any he has had in the past have put out their adult colors yet.