If you dont know yet, many of the spawn zones for herbs have changed. Particularly with Arthas' Tears and Purple Lotus. I know the later drops in felwood, and it used to be AT was in plaguelands, but it may be hidden behind a phasing? It's kinda interesting that for much of 200-300 you are dependant on rare as hell herbs - goldthorn and AT/PL. Each goes for 5-8 gold on the AH (each) currently.