After combing through all the books I have to agree with The Dark Wanderer, the only spell that lists difficult terrain by name that is Instantaneous is Shatterfloor from the Spell Compendium.
That being said there is a second Instantaneous spell that might provide what you are looking for if you word/describe right and the terrain is rock/stone. The Stone Shape spell from the Player's Handbook states that you can mold up to a 10 cubic foot + 1 cubic foot per level of rock into any rough shape. It is a Cleric 3 spell.
In the 1 minute/level class I found only one that might provide movement hindrance. In the Complete Divine book there is a Cleric 3 spell called Briar Web with a 20-ft radius that hinders movement.
Under the 1 round/level class I found several spells that hindered movement as well, not as long lasting but something to think upon for perhaps modifying/creating your own spell(provided your DM allows) that can help. They range in Area from 5-ft square/level to 10-ft cubes to 20-ft radius. From Player's Handbook the basic Grease spell(Wiz 1) and Sleet Storm(Wiz 3). From Player's Handbook II - Scattering Trap(Wiz 3) and Vertigo Field(Wiz 3). And finally from Spell Compendium - Cloud of Bewilderment(Wiz 2) and Shadow Binding(Wiz 3).
Sorry I couldn't find anything better but hopefully these will provide some ideas that you can work with.