Here is a list of international art competitions
that are quite interesting from Artshow.com

[Painting on the Edge - Vancouver BC Canada]

Grand prize $2000. Deadline: June 21, 2013

[Peninsula Art League Annual Open Show - Gig Harbor, Washington]

Over $3,300 in cash and prizes. Deadline: June 26, 2013

[2013 Art Kudos International Juried Competition - Online Exhibition]

$4,000 in cash awards. Deadline: June 30, 2013

[6th Annual Lillstreet International Ceramics Exhibition - Chicago, Illinois]

$750 in awards. Deadline: June 30, 2013

[4th International Painting Annual (INPA 4) - Art Publication]

$1000 in cash prizes. Deadline: June 30, 2013

[Texas Photographic Society 26th Annual Show - San Antonio, Texas]

$1,500 in awards. Deadline: July 12, 2013

[North East Watercolor Society International Exhibition - Kent, Connecticut]

Approx $7,500 in awards. Deadline: July 20, 2013

[National Watercolor Society 93rd Annual Exhibition - San Pedro, California]

$30,000+ in Awards. Deadline: July 27, 2013

[Coral Springs Mullins Park Mosaic Mural Project - Coral Springs, Florida]

Budget: $30,000. Deadline: July 31, 2013

[SMART- Science and Math based Art Contest - Los Alamos, New Mexico]

$2,500 in awards. Deadline: July 31, 2013

[Meeker Classic Art Contest - Meeker, Colorado]

$3,300 in awards. Deadline: August 1, 2013

[Un-Inhibited: Art by Smart Devices - Brooklyn, New York]

$1500 in cash awards. Deadline: August 16, 2013

[Scottsdale Salon of Fine Art - Scottsdale, Arizona]

$17,000 in awards. Deadline: August 26, 2013

[3rd Annual Eco Arts Awards - Online art competition]

$6,000 in awards. Deadline: November 4, 2013