Sindragosa (edit: sheesh, no one even pointed out the spelling error in my title) - Arthas' own dragon. Frosty matron of surliness. Her whiny, hysterical emote of "Suffer, mortals, as your pathetic magic betrays you!" sticks annoyingly in my ears even now. And the one fight in T10 content where resistance gear is not yet dead. Of course, if you're a DPS DK, you have the good fortune of being able to pretty much ignore resistance gear - but we'll get into that in a moment.
Sindy is the next-to-last boss in Icecrown Citadel, the penultimate challenge remaining in normal and heroic modes prior to facing the Lich King himself. It's a reasonably fun fight mostly involving dps burns interspersed with proper placement of debuffed players. Are you prepared?
Pull/Phase One (ground phase): Pop your potion pre-pull, and summon your army as your tank is running in to pull Sindy. It should be up again in P3. Go ahead with all your dps cooldowns, including DRW/Gargoyle/ghoul. Obviously, dps from the side to avoid her various attacks that hurt. :) In the middle of the ground phase, She'll do her Icy Grip ability and pull in the raid. The rest of your group will be frantincally running out to avoid getting blasted by Blistering Cold. You? In your frost resistence-less gear? Laughing as you slowly walk backward to max melee range, dpsing all the way. Give it about a two count, then pop your Anti-Magic Shell. If for some strange reason AMS is down, you can also survive the blast of cold with Icebound Fortitude, but I would probably run out if AMS isn't available. Try to make sure just before she takes off that you refresh your diseases so they can fully tick while she's flying - I often find I have to skip one Scourge Strike to make sure she's properly diseased (or Oblit, or Heart StrikeX2).
As to frost resist, the things that will kill you are either easily avoided, controlled, or reduced by normal cooldowns. I started attempts with 2 pieces of resist gear, then one, then found I had no problems staying alive with zero resist gear - and I wasn't even a burden on the healers! Anti-Magic Shell, line of sight, IBF, and even Death Strike - there are all your friends! Know them, love them. :)
P2 (air phase): Run to designated Tomb location. like most groups, we have a pre-set drop location for each person getting Tombed on the stairs. Make sure you recall your ghoul (if up) with you or he'll die from frost bombs. I also refresh my bone shield while running back to stairs, as bone shield charges are consumed often in this fight and you won't lose any dps refreshing it then. Sorry to you blood/frosty types that lack it. :) You know to stay away from the players with a frost beacon, but hopefully you know you can actually run back in immediately before the tomb actually forms - that way as soon as it's targettable, you're hitting the first one. Our tombs are close enough together that I pestilence to all of them, drop Death & Decay, and single target the first tomb. We ride the edge of killing them too soon or not soon enough; ideally you kill each tomb the instant a bomb goes off, then move to the next, and kill the last tomb the moment the final bomb goes off. That way everyone is broken out and max dps can resume on Sindy immediately. Burn hard and hopefully you get her to P3 with only two air phases.
P3 (ground phase): I usually use my gargoyle/drw/ghoul as soon as it's back up, but if you haven't used it yet, it should be ready by now. Your Army should be ready (for unholy anyway) shortly; just use it as soon as you can. My raid has melee on tomb duty, but I can usually skip every other tomb and stay and dps the boss (the other DK and I alternate killing tombs and hitting Sindy). Obviously, you need to be careful to let mystic buffet stacks drop. In addition, make sure to let Permeating Chill stacks drop too, especially given that you're in no frost resist gear. Occasionally, my health drops low enough that I Death Strike to get some health back before I head to the next tomb. BURN THE BOSS! She dies! Win! Usually around 4-5% we stop breaking people out and just burn the boss.
To sum up: DPS the adds in the correct order as quickly as possible. Stay away from things that will kill you. Spread diseases. My dps on this fight is poor compared to others, but if most of the adds are tanked closely enough, it's not too bad.
After that, the eponymous Lich King awaits!