I was looking to work on my character a bit more today, but can't find Chi Master or Shamanism in the list of edges anywhere...I'm using the Savagepedia and the free test drive rules.
Chi Master and Shamanism are both arcane backgrounds. So the edge in savagepedia/test drive rules is just Arcane Background.
Basically, the way it works is: you take Arcane Background as an edge, choosing at that time what "flavor" of magical powers you possess. (The most information they have about this in the Test Drive Rules is under Powers. I thought there was more in there, but I was mistaken). I'll try to explain how Arcane Background works basically here. If you decide on one of the Arcane Backgrounds I'll send you an ~6 page document with more details for that specific background from the Deadlands Reloaded book.
So, for Deadlands, when you take the Arcane Background Edge, you have 5 choices: Miracles, Shamanism, Magic, Weird Science, and Chi Mastery.
Each of these Arcane Backgrounds works similarly on a basic level. You get access to "Powers" which are the spells/abilities of all Arcane Backgrounds. The baseline rules for the powers are the same for all Arcane Backgrounds, but the idea is that you customize the "Trappings" of the power to fit whatever Arcane Background/Spell-effect you're going for. (see below). Additionally, each power (generally) has access to "Power Points" which are sort of like the mana you have to cast spells. And each background has an arcane skill which it uses to cast spells.
When you want to use a power, you decide what power you want to use and spend the power points to activate it. Then you roll your arcane skill vs. target number(TN) 4. If you succeed the power works, if you fail the power doesn't work. If you get a raise, usually you get some extra benefit. For targeted spells (like Bolt below), that roll is also your targeting roll (like you were shooting the target, with all relevant penalties/bonuses applied to see if you hit).
So, that's how they're all the same. But each Arcane Background is also a bit different. Mostly in this thread I've already talked about the differences. I'll talk a bit about how the powers are different for each AB here, then provide the quotes where I talk about it earlier in the thread.
So, Bolt for instance is the basic attack power. It shoots 1-3 magical bolts dealing 2d6-3d6 damage depending on power points spent. For Trappings, a Mad Scientist might have a "lightning gun" that shoots out lightning. And trapping-wise, it might require bolts to be fired at different targets within 3" of each other (think lightning arcing from one target to another), but targets wearing lots of metal suffer a -2 to all actions for the next round.
Additionally, not all powers are available to all Arcane Backgrounds. You can see an easy list of powers available (without effects)
here.
The excel file I linked previously has a list of all powers with a brief description of their effect in it. ([ulr=http://www.peginc.com/forum/viewtopic.php?t=11202]here[/url]'s the link again)
You get some [number of powers] when you take an Arcane Background Edge (explained below). You can also take the New Power edge to get access to another power, the Power Points edge (once per rank) to get 5 more power points, and the Rapid Recharge/Improved Rapid Recharge edges to recharge power points quicker. There are other edges available to each of the arcane backgrounds, if someone takes one, I'll fill them in on the specifics.
When you purchase an Arcane Background you get a number of powers dependent on the type. You also get a different number of power points and some sort of drawback. You didn't ask about the other 2 things, but here's the basics for Deadlands:
(I'm 90% sure this is correct)
Miracles (i.e. Blessed): have access to all powers, and don't use power points. Suffer a penalty to casting depending on rank of power being attempted (-2/rank including Novice), and suffer fatigue if they fail. Must adhere to a rigid moral code, or lose some power temporarily.
Shaman: 2 powers, 10 power points. Need to perform nightly rituals to appease the spirits. Can get away with not performing them for a bit if they follow the Old Ways Oath. Regenerate power points faster under the open sky.
Magic (Huckster): 3 powers, 10 power points. Shaken with a roll of 1 on the casting die. Regenerate Powers slowly (1/3 hours). May Deal with Devil for "free" power points, but that can also come with some drawbacks.
Mad Scientist: 1 power, 20 power points. Powers are in devices, which means each "New Power" comes with another device with its own power point pool. Devices explode with a roll of 1 on casting die causing 2d6 damage to anyone in a medium blast template (the device then needs repaired). Additionally, each time they take the New Power edge they get a random dementia.
Chi Master: 2 powers, 20 power points. Each power uses its own skill (linked to spirit).
the arcane skills are as follows:
Miracles (Blessed/Voodooist): Faith (Spirit)
Shamanism: Tribal Medicine (Spirit)
Magic (Hucksters): Spellcasting (Smarts)
Weird Science: Weird Science (Smarts)
Chi Mastery: Each Power (Spirit)
Those skills are almost exclusively for those Arcane Backgrounds. And really shouldn't be taken unless you're taking the Arcane Background, or possibly if you're planning on taking the Arcane Background in the future. (Note: The Chi Mastery power-skills CANNOT be taken until the power is taken.)
Anyways, hopefully that should be enough to know if you want to take an Arcane Background. You can only take 1 Arcane Background (it's one edge). So, if you do decide you want to take one, I can send you the information for that specific background (~8 pages in the book, I'll pull the text and it will be ~6 pages in word probably).
If you do need more information first let me know (or if anything is unclear above...which is likely).