How to: Blackwing Lair.

For these soloing guides, we'll start from the beginning.
I won't be doing Molten Core or Ruins af Ahn'Quiraj guide, they were doable at level 80, so figure at level 85.

So, Blackwing lair is the only level 60 raid whose bosses drop 120 -200 gold each (200+ for the two last), and a no-wipe run can take one hour, making it profitable.

Razorgore the Untamed
Gear: 0/5
Strategy: 2/5

The main problem is phase 1: you must manage to despawn adds without them respawning later.
Step 1: Quickly kill the two guards near Grethok. Don't kill him! Do not do too much damage on Razorgore, just enough to keep aggro. You can also misdirect him to a pet (in passive/stay stance) to avoid stuns and disorients.

Step 2 : Once the adds have spawned: jump to the very small ledge on the west side on the room, go to the end of it, turn your back and jump-disengage. Get on the platform, and make sure Razorgore has aggro on you (dismiss pet if you had it out). He should heal to full and go in evade mode.
After a while, Grethok will tell everyone to go back to their posts. Jump down before Razorgore resets, kill the guards, and take control of Razorgore with the orb.

Step 3:  Use Razorgore to destroy the eggs. Grethok should have aggro on him, and he melees hard (3-5K on the boss). Simply run away from him (as the boss) while destroy eggs is on CD, as to only be hit by the weak arcane missiles.
Whatever you do, it seems that hitting Grethok will reset the add spawn timer, so once Razorscale is Mind Controlled, don't use any of his dps abilities.

If adds spawn, restart at step 2 until they won't spawn again (unless there are 2-3 eggs still alive, in wich case you should have time to destroy them before the boss dies).

Phase 2 is a tank and spank.

Vaelastraz, 


Lashlayer,


Firemaw, Flamegor.
Gear: 0/5
Strategy: 0/5

Tank and spank. Vaelastraz should be doable in green gear.

Ebonroc
Gear: 0/5
Strategy: 1/5

Once he casts shadow of ebonroc on your pet, wait 2 seconds and taunt. He should put the debuff on you, giving you 8-10 seconds of free dps time.
You can also try to outdps his healing.

Chrommagus
Gear: 2/5
Strategy: 2/5

The safest way to do it is to kill a pack or two for the hourglass sand and use drums of forgotten kings to build up resistance. Then, prepot restorative potion (http://www.wowhead.com/item=9030) and pull.
Whatever your spec, you will want to have both cobra and steady shot in your action bars, since 4 of 5 types of magical damage are reduced at set time.
Dispel brood affliction: Bronze with the hourglass sand, and use a restorative potion if you have 3 or 4 others debuffs.
Use his weakness! Spam arcane shot if he's vulnerable to arcane, explosive shot of it's fire, and cobra shot (with rapid fire) if it's nature, Chimaera/steady/Aimed shot if it's frost or shadow. You should dish out massive damage: misdirect, feign death and misdirect as much as you can!

You should be able to kill him before you transform, if not, you will be MCed for five minutes.

If you feel you are about to transform, you can unequip your weapons and hope your pet will be able to finish him.

It's also possible to pull him, fight him until he has the fire(if SV)/arcane/nature debuff then reset the fight, and use a restorative potion to clear the debuffs.

Nefarian
Gear: 1/5
Strategy: 1/5

Phase 1: Multi-shot, disengage, frost trap, kill the adds.

Phase 2: misdirect Nefarian, finish the adds. Then deal with the hunter call (weapon breaks every 30 seconds).
You can unequip your weapon before each call.
Or use the heirloom bow.
Or use Jeeves (rich engineers only). But it will cost you a lot in repairs.
Or dps with your stick! (and your pet).
Or bring a few spare peashooters.

Explosive trap should be enough for the adds that arrive at 20%.