So I'm a holy priest, Realm: Shandris- Name; Vareline.
I just got to level 85 just recently. And before my item level was weak; so I wasn't able to join into Cataclysm heroics. Finally I had gotten my item level up but it was from buying stuff from the auction house. Healing priests need- Intellect and spirit correct?
I knew that. Although every time I have went into Cata heroic we've wiped tons, and I knew it was my heals. Where can I go to get stronger armor meant for heroics? And how do I know my gear is PvP or not? So many questions. And Hopefully I will receive some answers. Even if its where to get good gear from...
Link to character for examination if wanted/needed :
http://us.battle.net/wow/en/character/shandris/vareline/simple

I need some WoW geek answers here Please.

I've never healed, but you can get better armor for heroics through normal cata duns. PvP armor has resilience on it.

Just because you meet the minimal item level requirement to enter dungeons, it does NOT mean you are actually ready to do them.

From what I can see on the items you have listed, you need to REALLY work on your gear...

-You are wearing a lot of PVP gear (You can tell this because it has the stat "Resilience" on it.)
-One of your trinkets has Hit Rating, which is useless to healers

Also, the question I have to ask is that on the groups you've wiped with, was it problems with you running low on mana, or just weak heals? If it's mana, you definitely need a LOT more spirit.

To get better armor, keep running regular dungeons and use the justice points you earn to buy better gear... This is done in Orgrimmar. To find what dungeons give the gear you need, do a bit of research on wowhead.com and just farm those places until it drops.

Then finally; get a few more glyphs. Some glyphs can help you out a bit.

http://www.mmo-champion.com/threads/855585-Priest-PvE-Holy-Guide-(for-Beginners!)

this guide on mmochampion along with many others should help you heal effectively