Where can you submit your flash fiction for publication?
Try duotrope. (No, I am not affiliated with the site – except as a registered user.) http://www.duotrope.com/
Duotrope is an incredible resource for writers who would like to see their works published by others. With over 3,600 listings of fiction and poetry publications, they are certainly the largest, most comprehensive resource I know about for writers. Over 1,000 of these sites accept flash fiction. And it’s free. (Though they do accept donations to keep the site alive.)
Here is a short listing of some of my favourite flash fiction sites (ok, some I like more because they’ve published me!) :
365 tomorrows http://365tomorrows.com/
Every Day Fiction www.everydayfiction.com
Daily Science Fiction http://dailysciencefiction.com/
Daily Love http://www.dailylove.net/
Untied Shoelaces of the Mind http://www.untiedshoelacesofthemind.com/
Bartleby Snopes http://www.bartlebysnopes.com/
An electric tragedy http://www.anelectrictragedy.com/
Flash Fiction Online http://www.flashfictiononline.com/
Good luck and have fun!
And remember: Rejection is a part of writing. If you do not try, you will fail. Rejection is not failure, but rather the opportunity to try, try again!