Here is my build in some detail.

Race: I would use something stamina based. Imperial, redguard, wood elf. Something like that.

Armor: As stated in the post I use 5 whitestrake for that shield but a lot of people use hist bark instead. both are good in my opinion. I also use 5 footman which I get from getting the necklace and rings. Everything is stamina enchanted and the accessories are enchanted with feature cost reduction.

Weapons: My first bar I Use the master sword for heals with puncture and just any shield. You could use a crafted weapon set or endurance/agility set but I'm no perfectionist so I don't grind for them. They would be ideal though. Second bar can really be any weapon. I still use a sword and shield to keep my armor up and just use it as my execute bar and heal bar when I get vigor unlocked.(hate doing pvp since I'm not part of a guild)

Stats: everything into health

Abilities 1st bar: Sword and Shield
Puncture(pierce armor)
Dark Exchange(dark deal)
Shield Charge(shielded Assault) or Defensive Posture(Absorb Magic)
Lightning Form(thundering presence)
Bound Armor(Bound Armaments)

Abilities 2nd bar: Bow currently, change it all the time though.
Acid Spray
Mages Wrath
Vigor(when I get it), Using Encase at the moment
Thundering Presence
Bound Armaments

Champion Points:

I change this up a decent amount too but I basically dump all into block skills and stamina regen. Test it out and see what works best for you.

I don't play a sorc tank, so I can't help there...However, you should check out the guild recruitment section of the forums to find a good guild for you and your friends to join (if you haven't already). If you go back to the forum home page and scroll all the way down, the guild recruitment sections are broken up by platform & server. Good luck!

I play a breton Sorc magicka tank. Been tanking the new vet dungeons with *almost* no issue.

40 pts in Health, 24 in Magicka. 3 stats food buff.
Set 5P Seducer, 5P Footman, 2P Engine Guardian (Mace and shield in both hands)
Reinforced Chest, Legs and Shield, rest Infused, all glyphed in Magicka. The three jewels in Reduce block cost enchant.
The Lady for the Mundus Boon.
100 Red CP in Block Expertise, 12 in Heavy Armor Focus, rest in Bastion.
100 Green CP in Magician, 10 in Tumbling, rest in Arcanist.
100 Blue CP in Elemental Expert, 30 in Blade/Staff/Heavy Weapon whatever, 1 in Spell Erosion, rest in Elfborn.

(25k HP, 25k Magicka, 18k Stamina, 31k+ in Spell res and Armor - with food and buffs)

Bar 1 : Pierce-Amor, Hardened Ward, Harness Magicka, Defensive Stance, Bound Armaments, Negate.
Bar 2 : Inner Fire (unmorphed), Mystic Orb if my healer don't have it or Restraining Prison or Mage Fury, Dark Deal, Boundless Storm, Bound Armaments, Aggressive Horn.

Always use Pierce-Armor above anything else : the debuff is a must-have for the DDs. Inner fire is only for when you can't move/have to taunt from a distance.
I stack my shields, and spam my Mage Fury when I have it to help the DPS (I'm usually around 3k dps, yeah 8-) )
I usually use the Horn, unless I want to stun a pack, remove unwanted removable zones, things like that... with the Negate.

So when I say, *almost* no issue it's for a simple reason : the stamina. Dark deals does return stamina but it gets you out of block, so it's a no-go on most bosses.
So if your healer doesn't run with Repentance and/or Spear Shards, yes, it gets a bit difficult, you really have to time your Dark Deal and keep your stamina pots ready.
But if your templar heal knows his job, I found it really more fun and even easier as a Sorc magicka tank than a DK magicka tank in IC vet dungeons.

No trouble blocking no, but I do have 100 in Block expertise and 3 gold enchant Reduce cost block on the jewels.

And like I said, on bosses that hit really fast - like in the Prison the Overfiend (1st), or if you have Zombies on you while tanking the Flesh Abomination (4th), the shades phase of the Warden (last), yep, it's wearing a bit on my stamina pool. But the 4th and last, I have time to place a Dark Deal. On the Overfiend, no way to use it. So, I rely on my templar healer to repent the adds, or send me shards, or well.... my pots (and my dwemer pet) if the healer doesn't do the job ^^

Thanks everyone for the comments/builds. @Cathexis I look forward to seeing that video. PvP is really the one side im lacking a bit on.