So I am big into enchanting stuff. I literally have every enchantment in the book. Except the ones that aren't supposed to be in the book. I was looking at some items, such as the Amulet of Talos (Fortify Shouts: Reduce cooldown by 20%), and realized, I could probably enchant something for a higher percentage if I only had the magical effect in my big book of enchanting!

Is there any way one can add extra effects to their repertoire via the console?

As far as I tried, there's no way to do this. If you want to search yourself, there's an option:

Type help enchanting 1 on the console. That may list you possible console commands you may use. Me and myself coudn't find any way to do this. But, of course, you can do it better than me, I believe. ^^

But, anyway, there's a problem about enchanting unique items. I think you would have to re-enchant via console also.

Well, sorry if the answer wasn't as useful as I wish it to be. Hope I could help!

The only way you can increase the potency of the enchanting is to give yourself an enchanting skill of, let's say, 20000. Just type in console:

player.setav - Sets the Actor Value to amount.
player.setav - Sets skill directly to . Example: [player.setav marksman 50] sets your archery to 50.
player.setav - This also works attributes such as health, stamina, magicka, meleedamage, and carryweight. Note that certain attributes (such as carryweight) may revert to their original values upon loading a game.
player.setav dragonsouls - Set the number of dragonsouls.
player.setav shoutrecoverymult - Changes the cooldown of dragon shouts. The default multiplier is 1. A multiplier of 0 will cause instantaneous cooldown. Higher values will make shouts take longer to recover.
player.setav speedmult - Where equals your movement speed percentage as an integer value. (100 = 100%). To enable the new movement speed, you have to activate sneaking, running or drawing/sheathing your weapon(s) once. (NOTE: Using this can cause instability and crashes if you run into a new area too quickly)

And you can do just about anything else as well.

All very handy info! I was hoping to be able to get access to effects like 'Fortify Shout' and the 'Voice of the Sky' and so on, but I figure once the CK hits release all that will be revealed. I was especially interested in maybe getting a hold of the effects that Paarthurnax grants you when you meditate with him.

I would say learn to use the playerenchantobject console command in the mean time. On a side note there is also a playercreatepotion command as well and I believe they use the same effects to make things.

playerenchantobject