No, shipping isn't included...sorry. However, if you'd rather figure on $1.50 for each shrimp (X6 = $9) then add $7 for shipping, that'll save you a couple dollars 
Shipping costs the same for 6 or 12 shrimp so you actually make out better (price per shrimp) when ordering more. It's the weight of the water, not number of shrimp, that determines the cost of shipping.
2 shrimp per gallon will have minimal (if any) impact on the carrying capacity of your tank (bioload). Not that you should order 20 shrimp, just don't get too worried once they reproduce.

-Bill

Shipping costs the same for 6 or 12 shrimp so you actually make out better (price per shrimp) when ordering more. It's the weight of the water, not number of shrimp, that determines the cost of shipping.
2 shrimp per gallon will have minimal (if any) impact on the carrying capacity of your tank (bioload). Not that you should order 20 shrimp, just don't get too worried once they reproduce.

-Bill