Does anyone know if there's mods for morrowind that add extra spells to purchase or extra spell effects, like Midas or LAME or Fearsome Magicka does?

I'm thinking about making a mage character, but i'm hampered down by the lack of prefab spells. I know theres always spellmaking but its just not the same.

Only one I know of off the bat is scripted spells.

Scripted spells is an excellent and non-intrusive addition to any game -- you'll have to seek out the spell vendors to get access to the spells, but you'll find things like the Explosive Forces and Wall of Fire to be great fun, I'm sure. Off the top of my head, here's a few others:

There are some nice MWSE mods like Enhanced Summoning and Visceral Discernment that are also fun to play with.

There is a very cool looking [WIP] mod http://www.gamesas.com/index.php?/topic/1100908-wip-conjuration-overhaul/ which might be something to keep an eye on =).

Not only spells, per say, but I find Magical Trinkets of Tamriel IV to be lots of fun, particularly the necromancy system. Be sure to get John Moonsugar's patch for it, though.

Finally, though it is not done, I have a stable alpha release of my mod, Elemental Magicka, available for use/testing. If interested, see the link in my signature.

http://www.gamesas.com/index.php?/topic/1091351-alphawip-elemental-magicka/ is as close to Midas Magic as you'll get.
And boy does it look like fun. (I think I will test it actually)

edit: ah, I see NMZmaster has already mentioned it.