The French champions have not found a replacement for Sonny Anderson who joined Spanish side Villarreal in July.
They failed to seal a deal with young South African striker Lesley Manyathela on Monday and Aulas said Lyon were keen to sign either Bayern Munich's Pizarro or Viduka of Leeds.
Aulas has repeatedly been foiled this summer in attempts to sign a striker.
"We have collected a lot of information about Pizarro," Aulas said in an interview published by L'Equipe.
"We know him pretty well. It was him who sunk us in a UEFA Cup match against Werder Bremen a few years ago.
"Bayern didn't want to let him go until recently but since (Roy) Makaay joined (from Deportivo Coruna), things might change a little bit.
"We are reviewing the option to make Viduka come here too. We have offered a swap with (defender) Edmilson but he is not too eager to go to England."
Lyon had a disappointing start to the defence of their title when they lost 1-0 to Lille at the weekend.