The Source Masters can be found around Reaper's Coast.
The Source Masters
The Advocate
A powerful demonic lizard will teach you the source...for a price. Will you accept?
Almira
I owe you a debt, but I already know what you desire... and I intend to pay in full, right now. Tell me, do you know exactly what I am?
Hannag
Alright. Here's how you help: I can hold the Magisters off, but I can't put them down. Do this for me. Kill them all.
Jahan
All life, after all, sustains itself by consumption. Like the grass feeds the herd and the herd feeds the hunter, so you must feed, for instance, on these...
Mordus
To grow your source, to achieve your potential, you must embrace the Void.
Ryker
I'm not a generous man. But... I could give you what you seek, if you offer something in return. A completely fair exchange between sourcerers.