Can Shamans dual wield?Follow

Shamans can dual-wield with a minimum of 31 talent points in the Enhancement Tree.
Therefore, the minimum level of a dual-wielding shaman is level 40.

Shaman could not always dual-wield. They gained the talent after Patch 2.0.

Also know this, when you do duel wield, put WF/WF on BOTH weapons. And make sure they are 2.4 or slower prefering a slower off-hand, even if you have to use greens they will mean better DPS than say a fast blue.

Reason why you want it slow windfury weapon has a three second cooldown period. During this period, it will not proc again. Since no usable 1H weapons are slower than 2.9s (or 3.9s with flurry), this means that every single 1H weapon in the game will have at least one swing after its windfury that cannot proc windfury. Note that this means that windfury will proc less than the 20% promised on its tooltip. Handy reference chart:

3.0s normal, 4.0s with flurry = no swings wasted (no 1H weapons >20dps exist at this speed)
1.5s normal, 2.0s with flurry = one swing wasted
<1.5s normal, <2.0s with flurry = two swings wasted