All the brushes I created are now available on GIMPStuff :
http://gimpstuff.org/usermanager/search.php?username=rore&action=contents

cercles_thcourbes_thfeuilles_thgrass_thknots_thsnow_thsnow2_thsparkles_thspirales_thstar_th

Don't forget to check the other resources on GIMP Stuff :)