i think you should look for someone else. i think it would save you the heart ache bcus if he like you and u guys go out again and later on u guys break up again you will be hurt all over again .or if you found out he's single and u ask him out he will think you r desperate and cnt get another man and that is not cute its unattractive. if u still want to go thru with it here's what you do. get one of ur friends to ask one of his friends if ur ex like someone if they say they dnt know go tell ur friend to ask ur ex. if he ask why tell him that a girl ask her to ask ,if he ask who tell him, that girl he has class with( he will wonder who but tell him you dnt know her name and she just said she has class with you) and he will tell you if he like someone. he probably wnt tell ur friend who but you will know he like or do not like anyone.
you should look for another guy who u like,its plenty of fish in the sea.
well i wish you best of luck bye! :)