Thought it would be helpful to post up some DK macro's. The ones I use are very simple but work well for me. Also some of these can be found on www.wowwiki.com

General

Death Grip- This macro will cast death grip then chaines of ice to keep your enemy from running away. Press a second time and it will cast mind freeze and silence your target. Great macro when used against casters. Reason for having to press a second time is because mind freeze is a melee range and your target will usualy be out of that range when you cast death grip.

A bonus benifit as a frost spec chains of ice will cast frost fever and so you can skip casting icy touch.

#showtooltip Death Grip
/cast Death Grip
/cast Chains of Ice
/cast Mind Freeze

The following can be added into any macro that includes a CD and it will remove the warning on your screen.

/script UIErrorsFrame: UnregisterEvent("UI_ERROR_MESSAGE")

For cast this macro, I will nexample: Bladefist's Breadth is my trinket, so when my trinket is still on cd and ot get a warning.

#showtooltip Icy Touch
/script UIErrorsFrame: UnregisterEvent("UI_ERROR_MESSAGE")
/cast Bladefist's Breadth
/cast Rune Strike
/cast Icy Touch

Adding Rune Strike into any macro such as the above example is a sure way to cast it whenever possible and increasing your DPS

This applies more to frost spec since they will be the tanks, but any Death Knight can use this. Casts Death Grip if you need a taunt and you are trying to regain aggro, press again when Death Grip is on CD and it will cast Dark Command. Unholy Death Knights should change the reset to 25.

/castsequence reset=35 Death Grip, Dark Command

Frost

For a frost spec this will allow you to take full advantage of Deathchill every 2 minutes when your cd is up. Casting this once frost fever has been applied will cause extra damage. Casting after Pestilence and it will crit any enemy with frost fever as well.

#Blashowtooltip Howling st
/cast Deathchill
/cast Howling Blast

Another frost specced macro. Cast's Lichborne and heals yourself.

#showtooltip Lichborne
/cast Lichborne
/cast [target=player] Death Coil

Unholy

If you are an unholy spec the following is nice if you have put a talent point into your Master of Ghouls. This will cast Death Grip and Gnaw is your pets stun ability.

#showtooltip Death Grip
/cast Death Grip
/cast Gnaw

As an unholy Death Knight you know when you cast your deathgrip your pet automatically jumps to where the target was. Problem with that is your target is now in front of you and your pet has to run back. So on your pets action bar right click on the jumping ability will turn it off and will make the above macro more effective.

This is a nice macro for unholy once again. Casting Death Coil by hitting your hot key will cast it on your target, press alt+hot key and it will cast on your pet and heal it without losing your target.

#showtooltip Death Coil
/cast [nomodifier] Death Coil; [modifier:alt,target=pet] Death Coil


I have not been blood spec, so I do not have anything specific to them but some of the same ideas can be applied. I will update this when I have more to add. Also feel free to add any of your own.

the just my dk's list , some herb / min tracking written in

MACRO 16777221 "aoe" INV_Misc_QuestionMark
/cleartarget [dead]
/startattack
/cast [modifier] blood tap
/castsequence [nomodifier] reset=10 pestilence, blood boil, blood boil, blood boil, blood boil, blood boil
END
MACRO 16777217 "attack" INV_Misc_QuestionMark
/cleartarget [dead]
/startattack
/cast rune strike
/cast [modifier:shift] obliterate
/castsequence reset=12/target icy touch, plague strike, heart strike, death strike, heart strike, heart strike, death strike
/script
END
MACRO 16777222 "chains" INV_Misc_QuestionMark
/cast [target=mouseover, harm] chains of ice;
/cast chains of ice
END
MACRO 16777220 "cc" INV_Misc_QuestionMark
/cast [nomodifier] Mind freeze
/cast [modifier:shift] war stomp
END
MACRO 16777218 "dc" INV_Misc_QuestionMark
/cast [nomodifier, target=target, harm] death coil
/castsequence [modifier:shift, target=target, exists] reset=10 death grip, chains of ice, chains of ice
/castsequence [nomodifier, nocombat] find minerals, find herbs
END
MACRO 16777219 "tracking" INV_Misc_QuestionMark
/castsequence find minerals, find herbs
END

my attack macro is missing the /scriptuierrorsframe:clear() line.. not sure how it got cut out, but now that i try to fix it ... errors still wont clear.. have to fix that

i dont have any usefull macros