I would very much like to use a witch farm. I was wondering if anyone would let me know the co-ordinates of one they have built or that they are using. I would use it only when nobody else is doing so. Serious replies only, please. ~Seffy
If it's glowstone and/or redstone you're looking for, you may also consider a gold farm and trading the zombie flesh with a cleric. Witch farms in EMC can be a little slow going (20x20x16 2 spawn limit and other limits for lag), but villager trading is a bit OP here. You may also find a gold farm owner that has a stockpile of flesh they have not the time to trade.
I realize hours later that other people say my previous post when they mean: No. You are silly. But I mean it as: That seems like a Viable option.
emc is also happy enough to provide a list of those with good quality gold farms (at least the xp ones) here: http://empireminecraft.com/leaderboard/texp_month heh, ok, they are not all gold farms, but it's pretty likely.