This is a Half-Ogre built to trip. The min/max level is way into the red, so you may want to tone down the specialization a little.
Strength checks to trip opponents will be made with a +24 bonus (+8 Str, +4 Wolf Berserker, +4 Improved Trip, +2 Trip Attack, +2 Armbands of Might, +4 Size). Activate the ring to make that +30 and add rage for +32.
Half-Ogre Barb2/Ftr4/EWM3
Code:
Base Levels H-O Item Total
Str 17 +2 +6 +2 26 (+8)
Dex 16 -2 +2 16 (+3)
Con 16 +2 18 (+2)
Int 15 -2 13 (+1)
Wis 15 15 (+2)
Cha 9 -2 7 (-2)
Feats: 1,3,6,9 + 3 Ftr
EWP: SC, WF: SC, Combat Reflexes, Wolf Berserker (UE), Improved Trip, Large and In Charge (D), Power Attack
Get the Exotic Reach, Flurry of Strikes and Trip Attack abilities from EWM.
Some key equipment (max 66000 gp, level 11):
12325 Living Chain (MH) (+2, +4 Str check to trip)
18000 Ring of Growth (SS) (+1 Size category, +4 Str, -2 Dex)
4100 Armbands of Might (CA) (+2 Str checks, +2 damage bonus if -2 or more penalty from Power Attack)
4000 Gloves of Dexterity +2
4000 Belt of Giant Strength +2
48425 gp (23575 gp left for other equipment)
In the future you should consider adding the grasping (A&EG, +2) ability to the chain for +2 to trip and disarm attempts, and, if the DM allows it [I wouldn't], the sweeping (Magic of Faerun, +1) ability for +4 to trip checks. If you go with War Hulk, the Skillful (CA, +2) ability is downright broken. If you find yourself getting counter-tripped (?!) and forced to drop the chain, buy some Boots, Steadfast (A&EG, 6000) and become immune to trip and bull rush.
This equipment is intended to max out your trip ability. You may want to put off buying the ring or the chain for a few levels to afford a good vest of resistance (!), a magical mithral full plate and an animated shield. (Especially if you start at 10 level.)
Variants:
If the Wolf Berserker feat isn't available, or you want to expand your repertoire to take advantage of the chains disarm abilities, drop the barbarian levels for fighter levels and get Expertise and Improved Disarm. (You'll need 13 Int.)
(Just noticed your odd "three clases only" rule. That means no barbarian anyway if you want the War Hulk or any other PrC. More feats for you!)
The future:
I'd go for the War Hulk prestige class, from the Miniatures Handbook. Fun, fun, fun.
If you do, you'll want to drop a level of EWM and get Cleave (possibly instead of than Large and in Charge). You'll want all 10 levels (for the full +20 Str and the awe-inspiring Massive Swing ability) or only 8 (for a couple of extra fighter levels - pick cleave - and +11 BAB at level 20).
(There's an issue with the "No Time to Think" class feature of the War Hulk and the Exotic Weapon Master - technically you'll have 0 ranks of Craft: Weaponsmithing, which means that you'll technically no longer qualify for EWM, which means that technically you'll loose your EWM class abilities. That seems a little silly to me, and your DM may agree. If he doesn't then obviously EWM and War Hulk won't go together. )
Possible future feats (in no particular order): Great Cleave, Deft Opportunist (MH, need 15 Dex), Destructive Rage (CW), Hold the Line (CW), Improved Bull Rush, Shock Trooper (CW, tactical), Awesome Blow (MM), Mage Slayer (MH, CA), Weapon Specialization.
If you have questions, want some other ideas, and/or a more specific "build", or some more notes on tactics, let me know.