I like the ideas here, and indeed, with PvP and Dungeons, (especially the heroics, which are kind of hard to get into as an Elemental Shaman), you can get some great items.
Due to time constraints I won't put in links here, but here are some ideas to look for:
Worldfire Chestpiece from Dahllia
Area 52 Legs from Quest in Netherstorm
Thundercaller Gauntlets and Draenei Honor Shield, both found on AH usually for 20g or so depending on the server and intelligence of the auctioner
Shamanistic Helm of Second Sight is also good, from SMV's quest.
Biggest thing I'd suggest is a great 1-hd weapon... The Runed Song Dagger from Shattered Halls Ogre Boss. Great item, get spell dam and crit from it, and usually some useless items drop in the run, so save up the LPSs for the Spellpower chant (go for 30g a pop on my server currently)
I would commend all the pvp gear to you if possible... even with a weekend of bonus honor you should be able to snag a good piece or two that will help you round out the gear.
If you all are in Karazhan, I would commend the Big Bad Wolf's Head to you (it's one of two specific Elemental Shaman things in there, the other being the random drop Ring of Relentless Storms) and the biggest addition to my aresenal that I got on a 'please come help us out' plea from my Guild the first night we took down Illhoof... The Lightning Capacitor... if you want something that will work with the Elemental Shaman's abilities... this thing is TAILOR MADE!
It will proc off of any spell crit you create, even a Flametongue crit, and while it can no longer proc itself, the internal cooldown of 2.5s is quick enough that at long range the bolt and the LO bolt that follows after CAN both build the charge, I've been doing it all weekend on alliance that are running away from me, it all depends on the time from when the spell lands. Regardless, Elemental Shamans crit so much the thing goes off almost as often as the LO proc. TLC is great and I would recommend pleading with your raid leader into letting you get this trinket above all others. I know there are other caster classes built to critical builds, but with the crit rating and multiple castings available, I have had nothing but love for the shadow priest that passed on this so that I could have it.
Much love for Whissper.
The mentioning of pvp gear and dungeon gear, you can also try the Netherstrike gear from DS Leatherworking if you have the time and money. They are great additions to the gear build, but in total they take something like 36 primal airs and manas (why does Elemental Shaman stuff take primal AIRS!!! Blizz you are vile!) and three Primal Nethers, but the bracers can be made without a PM.
Good luck on it, and shoot for building slowly and working your way up. The crawl from 400-700 spell and 14%-20% crit won't happen overnight.
If you'd like, feel free to check out my gear, which is kind of in the same place as you, Kara-level, with some pvp and arena thrown in.
Check out Aegir on Echo Isles, Divine Retribution guild, Troll Shaman.
Cheers!