Sonce I don't usually have to, how do I put souls into gems? And where can I find the creatures to fill grand soul gems?
Cheers
DS

You cast soul trap spell into the creature you want to soul trap. Then kill it before the spell duration finish.

For Grand Soul Gem, better use soul trap Golden Saint and Ascended Sleeper as their soul value is higher. Golden Saint can be found wandering in plains in east side of vynderfell. Ascended sleeper can be found in Red Mountain area. You'll need to be level 20++ for them to appear.

(1) You need the Soul Trap spell. The "standard" soultrap it "touch" but you'd better create it yourself and make it "ranged", this will remove problems with casting a touch spell during a combat.
Once the spell is successfuly cast, you need to kill the creature before the spell wears off, keep this in mind when you select the duration of your spell.

(2) At any daedric ruins. The area with the ruins resets every time you enter it and contains (usually) 4 daedras. Therefore, check the daedras, enter the shrine, turn back, leave it (new 4 daedras will appear), repeat. It should not take it a long time before you get 2 Storm Atronachs.
Note: Golden Saints tend to cast Dispel Magic on themselves. If you haven't a soul trapping weapon or if you aren't enough fast then do not waste spell points on Golden Saints. Storm Atronachs cannot dispel the Soul Trap.

Can I used summoned creatures to fill soul gems?

Yes you can.

Now - where may I obtain a weapon which casts soultrap?

Umbra's sword has it. Go east(?) from the town with the scantily clad dancers (Suran? I rarely go there), and turn left when the road turns. He is on one of the short dead end roads into the mountain range.

Umbra is hard to kill, without good armor and good weapon (or spells) you loose. You can also seek a good weapon and enchant with a soultrap (this choice is much easier, but more expensive). The choice is yours [img]tongue.gif[/img]

Make a spell. ST is one of the cheapest in the game, IIRC. Just make one that lasts some 10-15 seconds and go kill a Golden Saint.
What level are you?

Avoid Golden Saints if you can - because of the Dispel Magic spell. You will cast soultrap - and the Golden Saint will dispel it almost immediately. You will need to cast it again, now, in the middle of a melee combat - and the Golden Saint will dispel it again. And so on ... And when you get your Golden Saints in the end, the woman in the basement of the Telvanni Hall will take them from you.

Why not specialize on Storm Atronachs? The woman wants them. They cannot dispel the soultrap and they are easier to get. Give the woman her atronachs and then start considering Golden Saints for your personal use.
Your stronghold is being built, you have enough time to get enough money for enchanting a soul gem filling special (enchanted with a short timed soultrap - the weapon is striking and casting again and again, Golden Saints have no chance to dispel it), and start your grand soul gem missions. The filled soul gems are now yours.