Book 6 in the Virtual Reality series.
From the back of the book:
"An evil and crafty nobleman has cheated you of all your wealth. But rather than starve as a beggar on the streets of Baghdad, you decide to leave in search of fame and fortune. Your travels take you to ghoul-haunted oases, magical palaces, lost cities of gold and uncharted isles full of mystery and danger. Threatened by bandits, fire wizards, thieves and fearsome creatures, you must risk all in your determined quest for justice."