This is essentially an update of Dirkdiglie's incredibly useful torrent "Ultimate Marvel - Complete (as of 10-17-08)".
This is everything, right here, in one torrent.
I've included a couple of reading orders to help you make sense of all of this.
Enjoy.Ultimate Comics Spider-Man #1-4
Ultimate Comics Avengers #1-4
Ultimate Comics Armor Wars #1-2

Ultimate Fantastic Four #1-60
Ultimate Fantastic Four Annual #1-2
Ultimate Marvel Team-Up #1-16
Ultimate Spider-Man Super Special (Conclusion to Ultimate Team-Up)
Ultimate Spider-Man #1-133
Ultimate Spider-Man Annual #1-3
Ultimate X-Men #1-100
Ultimate X-Men Annual #1-2The Ultimates #1-13
The Ultimates 2 #1-13
The Ultimates Annual #1-2
The Ultimates 3 #1-5
Ultimate Adventures #1-6
Ultimate Daredevil and Elektra #1-4
Ultimate Elektra: Devil's Due #1-5
Ultimate Galactus Trilogy
Ultimate Nightmare #1-5
Ultimate Secret #1-4
Ultimate Vision #1-6 (back-up stories)
Ultimate Extiction #1-5
Ultimate Human #1-4
Ultimate Iron Man #1-5
Ultimate Iron Man II #1-5
Ultimate Origins #1-5
Ultimate Power #1-9
Ultimate Six #1-7
Ultimate Vision #0-5
Ultimate War #1-4
Ultimate Wolverine vs. Hulk #1-6
Ultimate X4 #1-2
Ultimatum #1-5

Ultimates Saga
March On Ultimatum Saga
Ultimatum: Fantastic Four Requiem #1
Ultimatum: Spider-Man Requiem #1-2
Ultimatum: X-Men Requiem #1
Ultimate Captain America Annual #1
Ultimate Fantastic Four/X-Men Annual #1
Ultimate X-Men/Fantastic Four Annual #1
Ultimate Hulk Annual #1

Official Handbook of the Ultimate Marvel Universe: Spider-Man and Fantastic Four
Official Handbook of the Ultimate Marvel Universe: X-Men and The Ultimates
Official Handbook of the Ultimate Marvel Universe: Ultimate Secrets
Proper credit is due to the original scanners and uploaders.
Especially Dirkdiglie.