Mtg artifact destruction prevention?

Are you playing standard or casual? If you're in casual I highly suggest using Darksteel Forge. It makes all artifacts you control Indestrcutible (this would include itself). The only problem is a fairly high price to buy (roughly 8-10 dollars if I remember correctly) and it's high cost in game (9 mana). I usually don't cast it in any decks I use mine, however, because I usually have blue in those decks a Tinker and a couple of Master Transmuters to cheat it into play sometimes by turn 2 or three with the Tinker.

I believe in Standard, there's nothing for non-creature artifacts. There is Eldrazi Monument, but that will be rotating out soon. Well, I suppose you could do Xenograft + Knight Exemplar as well.

Outside Standard, there is the third ability on Elspeth, Knight-Errant, or a card called something like Darksteel Forge.