An obsessed fan of Delta Goodrem has been convicted of stalking after he went to the singer's home five times in one day, sent her 300 love poems and called out her name when she happened to come downstairs.

James Joseph Lafferty, 47, from Grafton, went to The Voice star's Sydney CBD apartment block on February 14 and tried to leave a Valentine's Day gift with the concierge but was told she didn't live there. He returned a further four times that day and was asked to leave each time.

On February 15, Goodrem looked out her window and noticed Lafferty was in a nearby park playing a guitar. When she later went down to the concierge desk to pick up a dress, Lafferty walked past and repeatedly called out "Delta, Delta".

Goodrem fled and could still hear Lafferty calling out her name after she left.