I had a Cleric that had huge rebuking abilities once. All the characters I put effort in have txt files with all or most of the planning involved.
Here's some notes I had saved, copy and pasted. Note that any bonus to turning level boosts rebuking level because they are the same ability (at least as far as that is considered).
So all this combined should work for you. However you need a firm grasp of how rebuking and commanding works to actually make use of all this. So READ THE REBUKING RULES CAREFULLY. The big tricks can be subtle.
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-turnings/day bonus sources:
nightstick: LibMort (7500gp), +4 turning attempts per day, 7.5kgp
reliquary holy symbol, MiC (1000gp), Up to +3 turning attempts per day, 1kgp
-Control limit bonus sources
rod of undead mastery: LibMort (10,000gp), double the amount of undead you can control via Animate Dead.
-undead effective HD debuff sources
rod of defiance: MiC (13000gp from LibMort) undead effectively have -4HD for turning/rebuking purposes.
lyre of restful dead: LibMort (3000gp), succeed on DC 15 perform string instruments check, undead within 30 feet have -4HD for purposes of turning for 10 rounds.
-Turning level bonus sources.
Divine energy focus (feat), Ghostwalk, +2 effective level. +2 on-top to turning checks and turning damage.
scepter of the netherworld (9000 gp), Libris Mortis, +3 to turning level.
"sacred" shield/armor special ability (+2 enchancement bonus cost- at least 18,000gp for a +3 shield with a +2 ability), +2 to turning level and turning check
phylactery/amulet of undead turning (11000 gp), DMG, +4 to effective turning level
Improved Turning (feat), PHB, +1 effective turning level
ephod of authority (800g), Magic Item Compendium, +1 turning level
flametouched iron holy symbol (750g) Eberron, +1 turning level
Talisman of undead mastery:(3000 gp) MiC, +2 turning level per charge spent, 3 charges/day, +1 turning level per extra charge spent.
rod of authority: (20576gp), Defenders of Faith, +4 cleric level for turning.
Item name, effective turning level increase, gold/level increase ratio
Defiance: +8, 13000 .615
Lyre: +8, 3000 2.666
Scepter:+3, 9000 .333
Sacred: +2, 18000 (+3 cost) .11
Sacred: +2, 18000 (+3 cost).11
Phylactery: +4, 11000 .3636
Ephod: +1, 800 1.25
flamtouched: +1, 750 1.333
Talisman of UM: +2, 3000 .6666
rod of authority: +4, .19