There are some monologues for men on this link that are from published plays:
http://www.freedrama.net/small1.html
They are:
"Fallen" - Short Dramatic Monologue from Published Script- Male (1 minute)
"Flowers from Phil" - Short Comedic Monologue from Published Script- Male (1 minute)
"Master" - Comedic Monologue from Published Script- Male (2-3 minutes)
"Humpty Dumpty Private Egg Hard-Boiled Detective" - Comedic Monologue from Published Script- Male (2 minutes)