Warrior/Paladin tanking gear

This will list off a general best in slot to gather as you get closer to the end of leveling up.  Their listed off at lowest value/easiest to get to highest.  

Once you have your gear assembled reforge it to optimize it.  

I wont add in the new heroic heroics yet.  Basically anything you find in there thats tanking gear will likely be the best.

Warrior Tanking Gear

Helm

6. Quest/Twilight Highlands: [Helm of Durable Hatred] (Horde) or [Gatekeeper's Helm] (Alliance)

5. Dungeon (HoO): [Helm of Setesh]

4. Rep/Wildhammer or Dragonmaw/Exalted: [Grinning Fang Helm] (horde) or [Crown of Wings] (Alliance)

3. Heroic Dungeon (HoO): [Helm of Setesh]

2. Justice Points(2200): [Helm of the Proud]

1. Engineering/525: [Reinforced Bio-Optic Killshades]

Shoulders

6. Quest/Twilight Highlands: [Wyrmhunter Spaulders]

5. Quest/Uldum: [Pharoah's Burial Spaulders]

4. Dungeon (GB): [Earthshape Pauldrons]

3. Justice Points (1600): [Sunburnt Pauldrons]

2. Heroic Bungeon (HoO) [Earthshape Pauldrons] 

1. BoE Drop: [Pauldrons of Edward the Odd]

Chest

6. Quest/Deepholm: [Gateshattering Hauberk]

5. Quest/Dungeon/Grim Batol: Breastplate of the Witness]

4. Heroic Dungeon (BC): [Beauty's Plate]

3. Justice Points (2200): [Chestplate of the Steadfast]

2. BoE Drop: [Icebone Hauberk]

1. Blacksmithing BoE: [Hardened Elementium Hauberk]

Gauntlets

6. Quest/Uldum: [Gloves of Gnomebliteration]

5. Quest/Twilight Highlands: [Grips of the Damned Mind]

4. Dungeon (HoO) [Fingers of Light]

3. Heroic Dungeon (SFK):  Gloves of the Greymane Wall]

2. Heroic Dungeon (HoO) [Fingers of Light]

1. Justice Points (1650): [Numbing Handguards]

Wrist

9: Quest/Uldum: [Ankh-Inscribed Bracers]

8. Quest/Twilight Highlands: [Dunwald's Finest Bindings] (ALLIANCE ONLY)

7. Dungeon (HoO): [Armguards of Unearthly Light]

6. Dungeon (HoO): [Alpha Bracers]

5. Heroic Dungeon (HoO): [Armguards of Unearthly Light]

4. BoE Drop: [Terborus's Rotating Bands]

3. Heroic Dungeon (HoO): [Alpha Bracers]

2. Heroic Dungeon (SFK): [Shackles of Undeath]

1. Rep/Ramkahen/Exalted: [Sandguard Bracers]

Belt

7. Quest/Uldum: [Hevna's Eye Socket]

6. BoE Drop: [Belt of Guardianship]

5. Heroic Dungeon (SFK): [Iron Will Girdle]

4. Justice Points (1650): [Girdle of the Mountains]

3. Heroic Dungeon: (LCotT): [Sand Dune Belt]

2. Rep/Guardians of Hyjal/Exalted: [Belt of the Ferocious Wolf]

1. Blacksmithing BoE: [Hardened Elementium Girdle]

Legs

6. Quest/Dungeon/Vortex Pinnacle: [Greaves of Orsis]

5. Quest/Twilight Highlands: [[Legplates of Riven Futures] (Horde) or [Legplates of Cooled Magma] (Alliance)

4. Rep/Earthen Ring/Honored: [Stone-Wrapped Greaves]

3. Heroic Dungeon (VP): [Legguards of Winnowing Wind]

2. Justice Points (2200): [Greaves of Splendor]

1. Heroic Dungeon (ToT): [Triton Legplates]

Boots:

6: Quest/Uldum [Femurbreak Stompers]

5: Quest/Twilight Highlands: [Gate-Breaker Treads] (Horde) or [Commander's Stompers] (Alliance)

4: Quest/Dungeon/Lost City: [Ramkahen Front Boots]

3. Heroic Dungeon (SFK): [Baron Silverlaine's Greaves]

2. Heroic Dungeon BoE Drop (VP): [Darksky Treads]

1: Rep/Wildhammer or Dragonmaw/Exalted: [Boots of Sullen Rock] (horde) or [Gryphon Rider's Boots] (Alliance)

Cloak

5. BoE Leatherworking: [Cloak of War]

4. Dungeon (GB): [Shroud of Dark Memories]

3. BoE Leatherworking: [Twilight Dragonscale Cloak]

2. Rep/Guardians of Hyjal/Exalted: [Wrap of the Great Turtle]

1. BoE Drop: Zom's Electrostatic Cloak]

Neck

4. Rep/Guardians of Hyjal/Honored: [Mountain's Mouth]

3. Heroic Dungeon: [Carrier Wave Pendant] (BC) or [Darkhowl Amulet] (HoO)

2. Justice Points (1250): [The Lustrous Eye]

1. Jewelcrafting BoE: [Elementium Guardian]

Rings

7. Heroic Dungeon BoE Drop (HoO): [Temple Band]

6. Heroic Dungeon (ToT): [Entwined Nereis]

5. Rep/Therazine/Rev: [Felsen's Ring of Resolve]

4. Heroic Dungeon (SC): [Phosphorescent Ring]

3. Heroic Dungeon (LCotT): [Ring of Three Lights]

2. Rep/Ramkahen/Rev: [Red Rock Band]

1. BoE Jewelcrafting: [Elementium Moebius Band]  (Not unique you can wear two)

Trinkets

12. Dungeon (GB): [Throngus's Finger]

11. Dungeon BoE Drop (LCotT): Impetuous Query]

10. Heroic Dungeon (GB): [Throngus's Finger]

9. Heroic Dungeon (ToT): [Porcelain Crab]

8. Heroic Dungeon BoE Drop (LCotT): [Impetuous Query]

7. Heroic Dungeon (SC): [Leaden Despair]

6. Quest/Twilight Highlands: [Za'brok's Lucky Tooth]

5. Justice Points (591): [Glyph of Indomitability]

4. ICC 10 man: [Unidentifiable Organ]

3. Alchemy (500): [Lifebound Alchemist Stone]

2. Jewelcrafting (475): [Figurine - Earthen Guardian]

1. Heroic ICC 10 man: [Unidentifiable Organ]

Ranged

7.  Quest/Twilight Highlands: [Muffled Blunderbuss] (Horde) or [Silenced Blunderbuss] (Alliance)

6. Dungeon (VP): [Thundercall]

5. Heroic Dungeon (HoO): [Slashing Thorns]

4. BoE Engineering: [Kickback 5000]

3. Rep/Baradin's Wardens or Hellscream's Reach/Rev: [Sky Piercer]

2. BoE Drop: [Spinerender]

1. Heroic Dungeon (VP): Thundercall]

Weapon

((Note:  There are any number of mastery/expertese heavy weapons that are servicable.  But for 'actual' tanking weapons your choices are limited.))

5. Quest/Deephom: [Questioning Axe]

4. Dungeon (GB): [Mace of Transformed Bone]

3. Dungeon (SC): [Elementium Fang]

2. Heroic Dungeon (GB): [Mace of Transformed Bone]

1. Heroic Dungeon (SC): [Elementium Fang]

Shield

4. Quest/Stormwind or Ogrimar: [Twilight Mirrorshield] (Horde) or [Truthbreaker Shield] (Alliance)

Dungeon (HoO): [Bulwark of the Primordial Mound]

Heroic Dungeon (HoO): [Bulwark of the Primordial Mound]

Heroic Dungeon (BC): [Shield of the Iron Maiden]

3. Justice Points (950): [Shield of the Four Grey Towers]

2. BoE Blacksmithing; [Elementium Earthguard]

1. BoE Drop: [Blockade's Lost Shield]