Architect Faheem Khalid Lodhi, 36, was found guilty by Sydney's supreme court of using a false name to buy maps of Australia's electricity supply grid.
He was also found guilty on two charges of inquiring about bomb-making chemicals under a false name and writing a "terrorism manual" with information on bomb-making, poisons and detonators.
Lodhi was cleared of a fourth charge relating to downloading aerial photographs for the purpose of terrorism. Prosecutors said he had downloaded pictures of Sydney military bases for an attack.
Lodhi had denied all of the charges, saying he had not planned to kill people or destroy property.
Strict terror laws
Prosecutors have previously linked Lodhi, also known as Abu Hamza, to a French national called Willie Brigitte who was deported from Australia in 2003.
Brigitte has been accused in a leaked French intelligence dossier of planning a terror attack "of great size".
Lodhi and Brigitte are alleged to have trained with Lashkar-e-Taiba, a militant Pakistani group that Australia has banned as a terrorist organisation.
Lodhi was charged under Australia's strict new anti-terror laws, which allow a maximum sentence of life in prison for the most serious charges. He will be sentenced later this month.