Scarecrow doesn't really have a lot of good arcs. There's a trade out right now called Batman: Prey where Hugo Strange tries to manipulate Crane and it bites him in the ass. That's about the best Scarecrow story I think I've seen.

He's got a lot going on in New 52 lately, but that's really hit and miss.

Honestly, Arkham Asylum's video game and the BTAS episode Over the Edge are probably the main things I'd recommend. Fear toxin is a hell of a drug.