Im no sonic/cold expert so will give a few general pointers I have found useful while pvping.
Hasten seems to be missing, it might just be a personal preference but I always try to work it in pre-30 to benefit from it whereever I pvp, sirens, WB or arena.
Not sure how much cash you got but you can really benefit from IOs and HOs in pvp. Even if you dont get a ton of them a few to increase the power of your slows, boost your damage with HOs or increase both recharge and tohit at the same time on aim really helps alot.
You havnt selected any of the shields or the massive +hp buff. If you pvp in the zones and got a brute friend around he will love you for them and you might pursade him to taunt someone that bugging you every now and then in return.
Since you got massive slow on your cold debuffs you might not need it but I usually got for the immob from the PPPs. Nothing is easier to kill than a stationary target and in the zones some people panic when they cant move and dont even fight back.
The sleep might also be useful alongside the disorient to get pesky blasters and other without sleep protection off your back. Sleep/Disorient, heal up, hit em hard with debuffs and laugh.
Hope it helps
I'm a fan of Hasten too. I wasn't too sure when to take it into this build, I think depending on the recharge of my other powers in general use I may or may not use it, we will see!
I'm not too familiar with any sets, but yes IOs would be helpful. Just tinkering around and can see that they might free up some slots for other things too. Didn't think of that.
I think my main reason for not taking shields is that I'm normally used to being a pure support character, so the rebel in me decided not to take any at all 
I think I'd get them later on if I really can't think of anything else, I'd like to be able to solo without too much trouble.
I was debating on Sleep, but with my very limited knowledge find that it doesn't work with me (or maybe I need more ACC). I read this in another guide and it put me off a little bit:-
[ QUOTE ]
Another cone, except this one has a stupidly long animation (the same as Decieve from illusion). It is a sleep, but it takes so long to fire that the blaster on your team could have probably killed the person you're trying to sleep before the animation is finished. I had this for a while, but found it pretty useless. Don't bother.
[/ QUOTE ]
Do people who PvP usually take methods to prevent Holds and Sleep (apart from the friendly CMs and Inspirations)?
Edited: Forgot to say, thank you for your advice 
Ah, if the animation is that long then it might not be worth it.
Everyone tries to protect themselfs the best they can against anything really. Stuns and sleep however are something thats very hard to protect from unless you got a power for it in your AT. Acrobatics protects from holds to a small degree but stuns and sleeps have no power like that which make them excellent as detogglers.
Hiya!
I really want to get into it and learn how to be good!
) and when I got past level 40 I got sort of stuck. Any feedback or advice on what to take after would be muchly appreciated. I'm also not very good at planning things in advance too so ... well I 'll let you see for yourselves 
I want to try and learn how to PvP, been playing this game for a while now but my only real taste of it has been getting completely squished as an Empathy Defender in the S4
I like to blast, I like Defenders (Storm especially) and I absolutely love Corrupters so wtih that in mind I have the following build. Sonic Attacks because I like the idea of -RES and Cold Domination because I know that as a Storm Defender I can at least annoy people whilst they try to step on me.
I'd like to point out that I have absolutely no idea what I'm doing (the idea of moving around in PvP didn't actually hit me until I read it in this forum
Villain Plan by Mids' Villain Designer 1.21
http://www.honourableunited.org.uk/mhd.php
Seventh Vehement: Level 43 Magic Corruptor
Primary Power Set: Sonic Attacks
Secondary Power Set: Cold Domination
Power Pool: Leaping
Power Pool: Fitness
Power Pool: Medicine
Ancillary Pool: Leviathan Mastery
Villain Profile:
Level 1: Shriek -- Acc(A), Dmg(3), Dmg(5), Dmg(7), Acc(15)
Level 1: Infrigidate -- Acc(A), Slow(9), Slow(33), Slow(34), Acc(34)
Level 2: Scream -- Acc(A), Dmg(3), Dmg(5), Dmg(7), Acc(15), EndRdx(23)
Level 4: Snow Storm -- RechRdx(A), Slow(9), RechRdx(17), Slow(31)
Level 6: Combat Jumping -- Jump(A)
Level 8: Shout -- Acc(A), Dmg(11), Dmg(11), Dmg(13), Acc(17), EndRdx(23)
Level 10: Swift -- Run(A)
Level 12: Amplify -- ToHit(A), RechRdx(13), RechRdx(21), RechRdx(34), ToHit(37), ToHit(43)
Level 14: Super Jump -- Jump(A)
Level 16: Health -- Heal(A), Heal(40), Heal(43)
Level 18: Howl -- Acc(A), Dmg(19), Dmg(19), Dmg(21)
Level 20: Acrobatics -- RechRdx(A)
Level 22: Stamina -- EndMod(A), EndMod(25), EndMod(42)
Level 24: Arctic Fog -- ResDam(A), ResDam(25)
Level 26: Screech -- Acc(A), Acc(27), RechRdx(27), Dsrnt(31)
Level 28: Benumb -- Acc(A), Acc(29), RechRdx(29), RechRdx(31), EndRdx(37)
Level 30: Aid Other -- Heal(A)
Level 32: Aid Self -- IntRdx(A), IntRdx(33), Heal(33), Heal(40), EndRdx(40)
Level 35: Sleet -- Acc(A), RechRdx(36), RechRdx(36), DefDeb(36), DefDeb(37), EndRdx(43)
Level 38: Heat Loss -- Acc(A), RechRdx(39), RechRdx(39), RechRdx(39)
Level 41: Shark Skin -- ResDam(A), ResDam(42), ResDam(42)
Level 44: [Empty] -- Empty(A)
Level 47: [Empty]
Level 49: [Empty]
------------
Level 1: Brawl -- Empty(A)
Level 1: Sprint -- Empty(A)
Level 2: Rest -- Empty(A)
Level 1: Scourge
<font class="small">Code:[/color]<hr /><pre>| Copy & Paste this data chunk into Mids' Hero Designer to view the build |
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|-----------------------------------------------------------------------------|
</pre><hr />
Thanks loads for your help in advance