Here's what my adventure spreadsheet says for levels 15+
Note #1: Anything from Dungeon #81 and earlier is 2e. The 2e adventures level listings are what they would reasonably be for 3e after I converted them.)
Note #2: I removed a bunch that I knew for sure off the top of my head were dungeon crawls... but lots more may still be in here. At least it's a start, though!
Against the Giants: The Liberation of Geoff (15th)
Akriloth, The (15th) - Dungeon #79
Anemones, Giant (15th) - Dragonlance Book of Lairs
Blood Feud (15th) - TSR Jam 1999
Bzallin's Blacksphere (15th) - Dungeon #64
Forgotten Man, The (15th) - Dungeon #75
Glacier Season (15th) - Dungeon #87
Man Forever (15th) - Dungeon #137
Rod of Seven Parts, The (15th)
Spoils of War (15th) - Treasure Tales
Strike on the Rabid Dawn (15th) - Dungeon #111
Throne of Iuz (15th) - Dungeon #118
Worms in the Exchequery (15th) - Dungeon #94
A Sword for a Hero (16th) - Treasures of Greyhawk
Enter Sandman (16th) - Treasure Maps
FRQ2 Hordes of Dragonspear (16th)
H1 The Bonegarden (16th) (Necro Games)
Into the Silver Realm (16th) - Dungeon #43
Preemptive Strike (16th) - Dungeon #74
Rock and the Hard Place, The (16th) - Dungeon #91
Sha'az (16th) - Book of Lairs (FR)
Changeling (17th) - Dungeon #32
Lear the Giant-King (17th) - Dungeon #78
Saurials (17th) - Book of Lairs (FR)
Sign of the Times (17th) - Treasure Maps
Trouble with Trillochs, The (17th) - Dungeon #80
Twisted Run, The (17th) - Dungeon #129
What We Face in Dreams (17th) - Ruins of Myth Drannor
A Darkness Gathering ("Illithid Trilogy" #1 of 3) (18th)
Masters of Eternal Night ("Illithid Trilogy" #2 of 3) (18th)
Dawn of the Overmind ("Illithid Trilogy" #3 of 3) (18th)
Diplomacy (18th) - Dungeon #144
Lich-Queen's Beloved, The (18th) - Dungeon #100
My Brother's Keeper (19th) - Treasure Tales
Ride the Lightning (19th) - Treasure Maps
WG6 Isle of the Ape (19th)
Dead Men Tell No Tales (20th) - Treasure Tales
For Duty & Deity (20th)
Razing of Redshore, The (20th) - Dungeon #92