How do you get a Soul Gem to have a soul with about 2400 charge in it on Elder Scrolls Oblivion

You can easily find the expensive and stronger soul gems by going to a mage guild become part of it and then you can search all the places for gems. if you want bigger go for getting all the recomendations and then go to the arcane university. there will most likely be very good gems and staffs you can take. i suggest that if you can go the deans dorm and if you can take his staff without stealing it then take that.