There are enough gems (except Malachide Gems!) and Ore's to find in the game, so don't be afraid to enchant and disenchant!
And if you have your Battle Tower your runners can also search for Gems or Ore's for enchanting weapons and armor.
And all weapons and armor you find with enchantments on, you can disenchant them and take the Formula (not the ingredients!).
Than you can sell that item( the value don't change without enchantments!) + the Formula too IF you don't wish to use it,
Or, you can use the Formula for enchant whatever you want.
Or simply change the kind of enchantment like you wish for each item you wish to use.
How to enchant? Go to your Enchanter (Dreavan : before defeating Laiken - or by Wesson or Radclif)
You must have a Formula to enchant something and there are Formula's for weapons, armor or jewellery!
What kind of enchantment you use is personal. I find for weapons "Increased .. Damage" very good, but there're much more.
And for the skills:
Magic Missile is nice, but if I must choose in your place for the 4 points left I go for Magic Blast
... Firewall is a good and strong spell
!
