Incapacitator

Summary
The Incapacitator focuses on incapacitating his enemies rather than killing them. To this end, he employs save or suck spells, charm spells, and annoying hinderances such as walls and pits. The Incapacitator's job is to make the DPR character's job easy - they should be able to waltz right in there and do their thing.

Attributes
Charisma > Constitution > Dexterity > Intelligence/Wisdom > Strength. As long as you buff up Charisma and keep constitution fine, you should be fine. Get intelligence high if you want skills, it's just a matter of preference. I would suggest this with a 20 point buy, after Gnome racial modifiers.

Str: 8

Dex: 14

Con: 14

Int: 10

Wis: 10

Cha: 19

It's relatively balanced, focusing on dexterity for ranged, AC and reflex, and constitution for HP and fort saves. You can, of course, get charisma all the way up to 20 instead, but just pump charisma every level and you should be fine.

Skills
Spellcraft, use Magic Device, and Fly are all must have. It's also worth pumping Intimidate, Bluff, and Diplomacy, given that your charisma modifier will do some of the work for you.

Spells
Level 0:

Daze

Detect Magic

Ghost Sound

Level 1:

Grease

Charm Person

Sleep

Color Spray Silent Image

Level 2:

Create Pit

Glitterdust

Web

Hideous Laughter

Invisibility

Scorching Ray - Here is one blaster spell to use when the time is right. It's not your game, but it will prove useful sometimes.

Level 3:

SLeet Storm

Stinking Cloud

Fly

Slow

Ray of Exhaustion

Haste - Because if you don't get it, your team will be pissed at you.

Level 4:

Black Tentacles

Confusion

Charm Monster

Resilient Sphere

Enervation

Fear

Telekenetic Charge

Level 5:

Wall of Stone or Force

Baleful Polymorph

Dominate Person

Overland Flight

Telekinesis

Hungry Pit

Icy Prison

Magic Jar

Level 6:

Summon Monster VI

Flesh to Stone Forceful Hand

Level 7:

Waves of Exhaustion

Reverse Gravity Grasping Hand

Level 8:

Prismatic Wall

Maze

Mass Charm Monster

Prediction of Failure

Irresistible Dance Clenched Fist

Sunburst

Level 9:

Time stop - Duh

Mage's Disjunction

Dominate Monster

Icy Prison

How to Play
Hang back and bother people. Drop pits, walls, charms. Make sure that you know what saves your opponents are weak to, as you will have plenty of choices for spells. Don't try to get greedy - you are a support character, but you can win the fight on your own.

Drawbacks
Obviously, your DPR is lackluster. You will need to rely on your friends to kill enemies.

Being small means a slower move speed. It will be hard to get out of melee if you find yourself in it.