in the spells_new, i believe the fields classes1 through classes16 indicate the level required for that particular spell to be cast by the class number found here:
http://www.eqemulator.net/wiki/wikka...akka=ClassList
example:
Holy Armor, 255, 1, 15, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255, 255
it's castable at level 1 by a cleric (2), and 15 by a paladin (3).
so, yeah... you should be able to construct a query to determine which spells would ever be usable on your server by looking at class/level restrictions.