Mostly because you cannot.
Maybe I am missing something, and maybe there is a rational explanation for all of this, and in either case, I will be more than willing to revisit this post, or completely retract if if someone can provide those absent details. But, for the time being, here is how it is.
Back on 05APR12, I placed an order for one of their Yugo Type 1 AK Pistol Grips in Walnut for my new Vera. As you can see, their online storefront clearly shows 17 units in stock at the time of writing this post. Shortly after placing the order, I received an order confirmation email from Weaponeer.net indicating that they had received my order and would be processing it shortly.
Since then… nothing.
In fairness, my credit card has not been charged; however, they have not responded to an email I sent to the address that sent me the invoice (gary (at) weaponeer.net), nor the email address they say to contact them at (boss (at) weaponeer.net), nor have they responded to a direct message on their forums (and, yes, I had to go out of my way to create an account on their forums to try to contact the admin account).
Look, folks, I am trying to give you my money, and you are making it damned hard for me to do so.
Unless you are willing to wait – apparently forever – for your product, I would recommend finding a source other than Weaponeer.net, which is rather unfortunate, honestly.