You can check out AKVIS artwork to convert your digital photos into oil painting. Actually, I don't have that much idea of any application which converts photo to oil painting as if I wanted to have any oil painting of my clicks then I go for real an artist, who converts my best clicked photo into art.
HI, You could try out Corel´s program called Corel Painter. www.corel.com/painter Here a tutorila on the subject http://digital-photography-school.com/art-photography-how-to-create-an-oil-painting-from-a-photo-with-corel-painter/