Although many of the Arcane Items are cool, its important to keep in mind that you're going to be a little limited due to only taking a sorceress or two in your army.
Book of Ashur
Not really going to help you much. Especially not for its points cost. Pretty poor item.
Not very good with the changes to bound spells. I guess you could use it to have a single sorceress cast Power of Darkness more than once (maybe?), but it's going to be easier to cast the spell yourself, and since you're pretty likely to get it off these days, this item is just a waste.
You're paying a high amount of points to try to damage an opponent's wizard. I don't really think it's worth it- the points spent here are better spent on trying to get more offensive magic out of your own sorceresses, I think.
Scroll of Leeching
This scroll is kind of cool, but I don't think it's going to be powerful or useful enough to warrant its cost. You certainly won't be putting it on one of the 1-2 sorceresses you're taking.
Sivejir's Hex Scroll
Pretty funny, but another scroll that's just not worth taking. Players likely will be running higher level wizards to take advantage of the bonuses provided by their level, meaning you're not likely to see this work.
I'm not sure. A lot of players are talking about running this on a cheap flyer, flying next to your opponent's lines, and then throwing every die you can at a spell for it to go off, hoping that the miscast causes additional damage to the unit near the wizard. I don't like it. It feels against the spirit of the game, but I bet people end up seeing that. I personally can't see myself using it, but if you're interested, do it on a Supreme Sorceress (on 7 die, this trick will always work) with the Pendant of Khaeleth. You'll get it off, and likely survive the miscast to go and cause havoc later on. There are a few ways to stop flying sorceresses before they can pull this off, but there are other ways to get it to work too. Of course, it's possible that it won't do enough damage to warrant trying this. Hard to say at the moment.
Wand of Jet
Not so good. Use the Sacrificial Dagger instead.
Has a pretty good chance to kill any Dark Elf sorceresses that tries to use it. Dark Elves have their own ways to generate more dice as well. I would skip it.
Staff of Sorcery
Might be worth it, but I think Dark Elf magic users should be equipped more offensively. Especially higher level magic users, who are going to be more effective than a level 2 Sorceress with this item at dispelling spells.
Not worth it. You want your spells to go off, not try to salvage something useful after it's been dispelled. Use your points to get a better item.
Still a great item. Some spells have very short ranges, and using this you can extend your ranges without having to try for the harder-to-cast versions of those spells. This is definitely a top 2 Arcane Item for Dark Elf players.
A free Power Die is actually handy since it's hard to say how many you're going to get each turn. Power of Darkness is the better alternative here, of course, but if you're running enough Sorceresses, you may as well take this. Probably not for normal sized games.
I'm convinced this is going to make Dark Elves THE scary magic race. There's a few benefits- it's a free die to every spell that sorceress casts, for the cost of a single Dark Elf soldier per spell. You get to see your roll before choosing to use the item as well. That's key. You can make sure to successfully cast those 'off by one' spell rolls, you can be very efficient in casting Power of Darkness, and you can see your risk for Irresistible Force/Miscasts. It's just a great item made even better by the changes to the magic phase.
A onetime help on the miscast table. No thanks. Take some protection from the results instead.
Only taking one hurts, but it's still helpful to take it since magic is SO powerful now. You never know when someone will roll a 20-something on a spell without IF, and this is your only protection. Worth taking.
Not necessary if you're a Dark Elf since the Sacrificial Dagger and Power of Darkness give you plenty of dice.
Tome of Furion
Not bad, but it's hurt by the fact that there are better magic items you could take.
Sceptre of Stability
First, it's Arcane, which is sad because you have better Arcane Items. Second, you have the Seal of Ghrond, which is more useful over the course of a game. I don't see much place for it.
Alright, 15 points to slightly increase the chance that ONE of your wizards generates a die through channeling. Don't take it.
Scroll of Shielding
This is actually pretty useful, but I don't think you're going to see it widely in Dark Elf lists because there are plenty of good Arcane Items here. Perhaps if you're running Sorceresses solely for defense, but it still wouldn't be the first item you take. Not likely to see use.