Well, not a shaman, but I've been equipping one in your level range recently, so here's some advice from my end.
Augments: Well, a good place to start for some basic basic stuff is the Scout Madu quests in Goru'kar mesa - he gives a series of tasks starting with "Parlay with the Dromrek" which should be completable at your level, is repeatable, and gives at least two or three useful augs. Additionally, if you still need mana regen, you can do the enormously easy Ogre Relics quest from Historian Pewdri in Crescent Reach. From there, you'll need to figure out what foci you need (and try to plan ahead, when possible. Level 66 isn't that far away.) and see if you'll need to get augs for those. After that, well, level to 63 and start filling out your inventory slots with DoN HP augs. ;P
Primary Weapon: First off, don't concern yourself too deeply about "is my primary weapon a weapon." At this point, your melee contribution is questionable, and, as you said, you've always got your trusty soulstripper to fall back on, which, honestly, when augged with a proc aug of some sort (maybe another lifetap), is about as good as you're really likely to want. For other primary slot options, a good one that seems surprisingly cheap on my server is the Mageblade, which drops from a couple of the mini-boss nameds in Arcstone, but is attuneable, so often available in the bazaar. And since the minis in question spawn hourly, and were, at least, for a while, getting whacked often for cloak marks, there should still be some of these around. Goodish stats, and hey, Mana regen 2. Don't knock it.
Shields: You're right. It is important to have a proper SHIELD in your offhand, and no, just having AC doesn't make something a shield. There are a couple of ways to tell. #1: It's a pretty safe bet, overall, that if it looks like a shield and is named like a shield, then it's a shield. That's not failsafe, but it'll rule out the vast majority of non-shield possibilities. #2: If you can bash with it, it's a shield. Not too helpful for a shaman, since you don't get bash, but you could ask other people on the subject. #3: You can go look at the item data in . If you look at the entry for, say, I dunno, the you'll see that the itemtype is "shield". Now, I'm not 100% positive that the itemtype field on the MAIN page is accurate, so I'd go one step further, click on the "raw" link in the upper right, and go down and look at the "ItemType" field. If the itemtype is 8, then it's a shield. Otherwise, it's not. That said, if you already have the , you're going to have a really hard time upgrading to a more stout shield for a goodly while. AC is king on shields, so don't let anyone talk you into trading out that 70 AC buckler for something with fancypants regen or something with less AC. Get your regen somewhere else.