From Spell Compendium:
Wave of Grief (Cleric 2) - I have no idea why making people sad is evil, but killing them isn't, but whatever. Not in your level range, but still a good area debuff I like to use.
Wither Limbs (level 4) - Deathbound domain only, but great flavor. Withers away and twists the arms or legs (your choice) of the victim.
Wrack (Cleric 4; Sorc/Wiz 5) - Just a Fort save or lose, but rather vicious and graphic. Victim is left prone, blinded, and helpless in agonizing pain. Even several rounds later once it's over, the poor person's still left shaken for several minutes. It's in no way a good spell, or a "fun" one to do to a PC and remove him from the fight. But it's so very evil. My evil Cleric loved using it on people that really pissed him off.
Death Throes (Sorc/Wiz/Cleric 5) - Explode violently when you die. Best when used with a Lich, to add injury to the insult of learning all that fighting was for nothing.

Doomtide and Crawling Darkness (Cleric 5) - Listing them together because both are just creepy and dark, but not outright evil.
Barghest's Feast (Cleric 6, Sorc/Wiz 7) - A very evil spell to use on a PC; read the Barghest entry in the MM if you don't know why.
Spider Plague (Cleric 6) - Summoning giant spiders seems like an evil thing to me.
Opalescent Glare (Cleric 6) - Gaze attack to kill or make people afraid.
Blood to Water (Cleric 7) - Does to the victim as the name; represented as 2d6 con damage.
Consumptive Field, Greater (Cleric 7) - Draw power from those around you that are dying...by draining what little life force they have left.
Evil Glare (Cleric/Sorc/Wiz 7) - Paralyze creatures with Gaze. Plus, it has Evil in the name.
Infernal Transformation / IT, Lesser (Cleric 7 and Cleric 4, respectively) - Polymorph into a Devil form.
Slime Wave (Cleric 7) - I just can't see a "good guy" unleashing a wave of green slime for some reason...
Symphonic Nightmare (Cleric/Sorc/Wiz 7) - Send people nightmares!
Brain Spider (Cleric 7) - Difficult to do stealthily if you want to use it out of combat due to all the components required. Though...invisibility + silent spell would work. Lets you read surface thoughts, memories, or thoughts on a subject of up to 8 targets for several minutes. Once per round, you can also try to give one target a
suggestion, which they get a new save to avoid each time.
Translocation Trick (Sorc/Wiz 4) - Switch places and appearance with another. Good for getting away by sacrificing a minion, or if the save is failed, as a readied action against the charging barbarian so he accidentally kills his best friend (whose place and appearance you've swapped).
Sensory Deprevation (Sorc/Wiz 4) - Block all of the foe's senses.
Shadow Well (Sorc/Wiz 4) - Like a weak Maze. Sends victim to a dark other plane for a few rounds, and he's scared when he returns.
Phantasmal Thief (Sorc/Wiz 5) - Invisible force that steals things.
Wall of Limbs (Sorc/Wiz 5) - One of those spells that just
feels evil.
Graymantle.... screw it. The entire lot of level 5 Necromancy options is worth looking over.
Fiendform (Sorc/Wiz 5) - As the name.
Probe Thoughts (Sorc/Wiz 6) - Look into the memories of people for information.
Illusory Pit (Sorc/Wiz 6) - If you can get over playing it comically ala "Road Runner," it could be a nice "evil" spell.
Every single level 6 Necromancy spell except Incorporeal Nova works well.
Extract Water Elemental (Sorc/Wiz 6) - Removes water from the poor victim, and if it kills them from damage, a water elemental forms out of the hollow shell that was her body.
Solipsism (Sorc/Wiz 7) - Both a cruel jab at a philosophical theory and a cruel way to leave someone helpless. Victim think only he is real and the all else is not, leaving him to stare in bewilderment.
Avasculate (Sorc/Wiz 7) - Already mentioned.
Kiss of the Vampire (Sorc/Wiz 7) - Become Dracula.