I am going to start a character who is very fascinated with the lands of Akavir, and one thing that is stopping me is that I do not have a complete list of items to collect.
So far, my list includes:
Akaviri Katana, and Dai Katana.
Mysterious Akavir
Blades armor

But I could swear there is more Akavir related items.

Pointed out by others:
The Madstone from the Pale Pass quest
Akaviri Orders
Ring of the Vipereye
Akaviri Warblade sold at Jensine's.
Akaviri Sunderblade sold at the Three Brother's Trade Goods.
Ruined Akaviri shield in the Pale Pass Fort.
Akaviri Warhammer, Generic Magic Item
Dawnfang/Duskfang

the madstone which you get from pale pass

The "Ring of the Vipereye" is Akaviri, and also the "Akaviri Orders."

The Akaviri Warblade sold at Jensine's.

The Akaviri Sunderblade sold at the Three Brother's Trade Goods.

The ruined Akaviri shield in the Pale Pass Fort.

The Akaviri Warhammer, a generic magic item. The warhammer is actually dwarven looking, although it's called Akaviri Warhammer.

Alright, thanks, I am sure there might be more, but I got a good amount to collect as it is now

My favorite sword

http://www.uesp.net/wiki/Shivering:Dawnfang

The armor used by the blades?

http://www.uesp.net/wiki/Oblivion:Akaviri_Fort_Key#Akaviri_Fort_Key

http://www.uesp.net/wiki/Oblivion:Undead_Akaviri_Soldier

http://www.uesp.net/wiki/Oblivion:Baurus%27s_Akaviri_Katana#Baurus.27s_Akaviri_Katana

http://www.uesp.net/wiki/Oblivion:Renault%27s_Akaviri_Katana#Renault.27s_Akaviri_Katana