@Silverchild79,
All the suspected hijackers were from Saudi Arabia, United Arab Emirates, Lebanon or Egypt.
United Airlines Flight 175:
Marwan al-Shehhi (from the United Arab Emirates)
Fayez Banihammad (from the United Arab Emirates)
Mohand al-Shehri (Saudi Arabian)
Hamza al-Ghamdi (Saudi Arabian)
Ahmed al-Ghamdi (Saudi Arabian)
They were the only people with Arabic names on the flight.
American Airlines Flight 11:
Mohamed Atta al Sayed (Egyptian)
Waleed al-Shehri (Saudi Arabian)
Wail al-Shehri (Saudi Arabian)
Abdulaziz al-Omari (Saudi Arabian)
Satam al-Suqami (Saudi Arabian).
There was only one other passenger with an Arabic name who was ruled out as having any role.
United Airlines Flight 93:
Ziad Jarrah (Lebanese)
Ahmed al-Haznawi (Saudi Arabian)
Ahmed al-Nami (Saudi Arabian)
Saeed al-Ghamdi (Saudi Arabian)
They were the only people with Arabic names on the flight.
American Airlines Flight 77:
Hani Hanjour (Saudi Arabian)
Khalid al-Mihdhar (Saudi Arabian)
Majed Moqed (Saudi Arabian)
Nawaf al-Hazmi (Saudi Arabian)
Salem al-Hazmi (Saudi Arabian).
There was one other passenger with an Arabic name who was ruled out as having any role.
The Hamburg cell and other conspirators
According to the 9/11 Commission Report, the terrorist attack itself was planned by Khalid Sheik Mohammed and approved by Osama bin Laden, with Mohammed personally choosing the hijackers, and bin Laden approving of the decision. This account is in dispute as bin Laden is not wanted by the FBI for the September 11th attacks. Sheik Mohammed and Abu Zubaydah became the organizers of the plot. Investigators say that Mohammed Haydar Zammar acted as the "travel agent" to Afghanistan.
Three of the hijackers, along with Ramzi Binalshibh, Said Bahaji, and Zakariyah Essabar were members of the Hamburg cell. After Atta, al-Shehhi, and Jarrah left for the United States, Binalshibh provided money to the conspirators. Riduan Isamuddin, aka Hambali, met with two of the hijackers in Kuala Lumpur during the 2000 Kuala Lumpur al-Qaeda Summit. Hambali also gave money to alleged 20th hijacker Zacarias Moussaoui. The members of the cell fled Germany before the terrorist attacks.
Some of the money that financed the terrorist attack seems to have originated from Ali Abdul Aziz Ali and Mohammed Yousef Mohamed Alqusaidi, who may be Marwan al-Shehhi's brother. Another conspirator is Abu Abdul Rahman. Tawfiq bin Attash, also known as Khallad, assisted the hijackers in many ways, and unsuccessfully sought a visa to enter the United States and participate in the attacks.
Interviews with detained al Qaida members have identified ten hijacker candidates who did not participate in the attacks for various reasons. These people were identified as Mohamed Mani Ahmad al Kahtani, Khalid Saeed Ahmad al Zahrani, Ali Abd al Rahman al Faqasi al Ghamdi, Saeed al Baluchi, Qutaybah al Najdi, Zuhair al Thubaiti, Saeed Abdullah al-Ghamdi, Saud al Rashid, and Mushabib al Hamlan, and Abderraouf Jdey.