PLEASE DO NOT COMMENT OR VOTE IF YOU HAVEN'T TRIED THE BUILD, UNLESS YOU HAVE TRIED THE BUILD I WOULD PREFER YOU TO KEEP YOUR THOUGHTS UNTIL YOU HAVE EXPERIENCED THEM.
Look at first Taric for this build. Second Taric is an alternate build in the works.
This is a support tank build for Taric. It focuses on healing, everything in this build works towards being able to heal more. Taric's passive Gemcraft gives him 7.5% of his damage back as mana. When Taric attacks Imbue's cooldown is reduced by 2 seconds. Imbue also get's 1.1x ability power added to healing. Taric's Ult. Radiance heals him for ~20-90 health/second and increases his damage by 30/60/90 and his allies damage by 15/30/45 when active. The best way to maximize all of these skills is to run in to team-fights head first! Turn on your ult and start whacking away at whoever is closest. Use your stun to help initiate on squishy targets and never stop healing and attacking(whoever you can your damage is less important than reducing the cooldown on Imbue). It is better to over-heal your teammates in a team fight than to hold off on using your heal.

Spirit Visage is a nice item to have as Taric, gives you a good cooldown reduction, some health, magic resist, and makes you heal and regenerate 20% more for yourself. This is cheap and effective.

Chalice of Harmony is a really good item for Taric. It gives a lot of magic resist, some small base mana regeneration and a huge amount of mana regeneration if your low mana. If your playing Taric rite you will end up with no mana all the time and low health too but this is not when you go back to base, this is when you start attacking minions and building up mana to heal yourself back to fighting strength.

Mercury's Treads are necessary for the 25% reduction from slows stuns etc. Taric needs to constantly be attacking and healing in team fights or he is useless, stuns are his worst enemy.

At this point you still are short on mana so a manamune is a good way to go, it has the potential for 1000 mana just as important its passive adds a percent of your mana to attack damage. The increase attack damage in turn increases the mana you receive from Gemcraft.

Next you need to build a Nashor's Tooth and in my opinion you should start with the Stinger. The increased attack speed will let you heal for a lot more because you can attack more and reduce the cooldown on your heal. Nashor's tooth is perfect for this build because it lets Taric attack more so he can heal more and gives him some mana regeneration along with ability power.

Rod of Ages is a good item if you still need to fill in your slots, it gives a lot of health mana and ability power which are all very useful to you.

If it goes to late game and you have extra gold replace Chalice of Harmony with Archangel's Staff. You won't get the 1000 mana but you will get a lot of mana regeneration, mana, and ability power.

You should get Dazzle first because it is more likely to save you early than your heal. Early game your Imbue is not very useful and you are very squishy. It is used more to keep you from having to go back to base to stay at full health than to save you. If you are laning with someone willing to buy a ward that would be a very good idea because you cannot take a gank.
After that put two points in your heal, it will make it much more powerful. Now one point in shatter, its useful extra damage and adds some armor. Get your Ult, Finish Imbue, Shatter, then Dazzle. Dazzle having more damage isn't very useful compared to Shatter doing the same amount but aoe + adding armor to you or armor reduction to your enemies. In team fights blow your Shatter rather than keeping it for armor, the armor reduction + damage to your enemies is more useful.

I highly recommend Cleanse + Cleanse point in mastery. If you use Cleanse effectively it can make a huge difference in your game. Basically use it whenever you need to a don't be shy about it. The second mastery is really your own preference, I put Flash because Flash is badass.

This build is all about team fights. It is better suited to a 5v5 game than 3v3.
These are the steps you should take when team fights are about to begin.

Click R, A and then closest enemy. This turns on your ult then attacks the closest person.
If the enemies target you and you are stunned or cannot attack an enemy immediately Cleanse you will go down extremely fast if you aren't attacking someone and healing your allies + yourself.
If anyone is below 70% health Q click that person, if not E(Dazzle) whoever is being targeted by your allies UNLESS there is someone like Nunu or Malzahar because your stun will stop their channeling which can turn a battle(duh).
Then W(Shatter). Shatter is better used to reduce enemies armor + hurt enemies then to boost your armor and your teammates armor.
Constantly attack whoever is closest, it doesn't really matter who your hurting what matters is that your attacking.
Constantly Q(Imbue) whoever needs it most or whoever is you can. If you are attacking it should be between 6-3 seconds cooldown before you can heal again and you must use your heal the second it is up.
Constantly W(Shatter) whenever cooldown is up. It will do pretty good AOE damage for reduce the armor of nearby enemies.
You can save your stun for anyone trying to escape or stopping channeling, no need to just use it its damage is minimal at best.
If a team fight is ending and people start to run you might need to turn off your ult. If you aren't able to attack anyone then your mana will deplete a lot faster and the mana drain from your ult increases over time so this is probably a good time to turn it off. The cooldown isn't long it will be back up in no time.

You are playing a support tank so your going to be attacked a lot, the 4% reduction to damage is very useful from Defense among the other defensive buffs. Put the rest in utility to more mana and mana regeneration.

Greater Mark of Alacrity, Taric needs to attack fast to reduce the cooldown of Imbue.

Greater Seal of Clarity, Gives a lot of mana regeneration, which is very needed since he is constantly using mana.

Great Glyph of Focus, Normally people would get cooldown reduction for Taric but his items eventually cover almost all the 40% (37%) so get some ability power to increase your heals.

Greater Quintessence of Force, More ability power more healing.

Use your Shatter to farm, thats another important reason to level it over Dazzle. Taric sucks at last hitting so farming can be pretty hard.

Ability Power 193 (4% from masteries)
Magic Resist 121 (6 from masteries)
Attack Damage 202.76 (66.76 from manamune)