I cannot find an item with fortify destruction on it, I've found fortify for all the other schools. Is there a guaranteed place/vendor that would have one? Pretty frustrated atm, and my enchanting is almost 100 so I'd like some reduced cost destruction spells.

Kill some Thalmor. Their robes are enchanted with what you need.

Tour the court mages until you find it.

I believe there is a certain fellow in Markarth

I will leave a pile of burning Thalmor in my wake, thanks!

Always hit the smith, pawn broker, and mage of every city you visit. You're bound to find something sooner or later (and usually sooner). If that's too long a wait, you could do the Forsworn Conspiracy quest and . The gear he gives you as a reward has some fortify destruction enchants.

You can't disenchant that stuff, though.

well punch me right in the face...

To add to this question, the Destruction robes you can buy also have a regen increase, if I disenchant these the enchantment has both Fortify Destruction and Regen.

Now if I want to enchant something with these does it add both of these enchantments? and If so, does it count as 2 enchantments or with the extra enchantment perk, can I add a 3rd?

There are two types of enchantment per magic school
1) "bigger" reduction in spell cost
2) "smaller" reduction in spell cost + mana regen

1 and 2 are each a single enchantment (even though 2 has more than one effect).

I tend to skip (2) and go for as many (1) enchantments as possible. With high enough enchanting you can get to 100% reduction. At that point you wouldn't even need magicka regeneration. With the level 100 Enchantment perk, there's enough enchantment slots to make 2 schools of magic absolutely cost free.

Thanks,

That means I am back on the hunt for a pure Fortify Destruction and Fortify Conjuration items to disenchant.

Check out Radiant Raiments in Solitude. They usually have loads of enchanted stuff.