(For those of you who have been collecting Valyrian's replicas of the weapons from the novels, yes, that line is continuing as well, but Jalic has also entered into this deal with HBO to produce limited edition replicas of the blades from the show. So it is entirely possible that eventually there will be two variant 'editions' of the same blade, though it has not happened yet).
Here's the Catspaw Dagger:
A handsome blade, I think. Though rather completely different from the dagger in the books, which was far plainer (though made of Valryian steel, with a dragonbone grip). It can be ordered here:
The Sword of Robb Stark is never described in any detail in my novels... but if I ever had paid it any mind, it probably would have looked quite a lot like the one seen in the show, which Valyrian Steel has replicated. So this one can almost be considered "novel authentic" as well as "show authentic." Here 'tis:
You can order Robb's sword at http://www.valyriansteel.com/shop/swords/robb-stark/prod_21.html
Both weapons come with a Certification of Authenticity -- though, please note, not a SIGNED CoA, since these derive from the TV show, not the books. The weapons from the ICE & FIRE range, as opposed to the GAME OF THRONES range, are the only ones that include my illegible scrawl.
Speaking of which, I should also note that Valyrian Steel's replica of Needle, the sword of Arya Stark, is now SOLD OUT, like Longclaw and Ice before it (a second version of Ice, based on the HBO version, is forthcoming, but the novel version is all gone). These blades are all limited editions; when they are gone, they are gone, and the price on ebay and other collector sites tends to skyrocket. Robert's Warhammer and the Night's Watch dragonglass dagger set remain available from Valyrian Steel, but stocks are dwindling, so if you want one, don't wait too long.