New to NL and these overbets confuse me

[Ainex]

Massive overbetting on the flop confuses me and I have a hard time putting villains on a push range. Can you help me define his range here?

1/2 NL SB has $196 and I cover.

UTG limps, SB completes, I make it $12 with A[img]/images/graemlins/club.gif[/img]J[img]/images/graemlins/spade.gif[/img] in the BB. UTG folds and SB calls.

Flop is 3 [img]/images/graemlins/heart.gif[/img]8 [img]/images/graemlins/spade.gif[/img]9 [img]/images/graemlins/heart.gif[/img]

SB checks, I bet $20, Villain pushes all-in.

So what does an unknown villain push with here? It screams weak made hand or big draw to me and yes I have a crap hand vs either of those but what do you think should be in his range? What if the 8 was a 6? What do I do if I have A8 (with and without A [img]/images/graemlins/heart.gif[/img])?