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

[Pennsylvania Watercolor Society 34th International Juried Exhibition - Warren, Pennsylvania]

Over $10,000 in cash and merchandise. Deadline: May 25, 2013

[Dave Bown Projects 6th Semiannual Competition - Online exhibition]

$10,000 in cash awards. Deadline: May 30, 2013

[The Social Media Show 2013 - Northbrook, Illinois]

$2000 purchase prize and numerous other prizes. Deadline: May 31, 2013

[American Plains Artists 29th Annual Juried Exhibit - Scottsdale, Arizona]

Over $22,000 in awards. Deadline: June 1, 2013

[The Cord Prize - Online exhibition]

$11,500 in awards. Deadline: June 2, 2013

[4th Annual Nature and Wildlife Exhibition - St Augustine, Florida]

$5,000 in awards. Deadline: June 3, 2013

[Open Water 2013 Water Media Exhibition - Calgary, Alberta Canada]

$11,000 cash and products. Deadline: June 7, 2013

[International Open Call for Photographic Urban Landscapes - New York, NY]

Over $2,500 in awards. Deadline: June 15, 2013

[Laumeister Fine Art Competition - Bennington, Vermont]

$7,000 in awards. Deadline: June 16, 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

[Meeker Classic Art Contest - Meeker, Colorado]

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