The Lizardmen have some of the best "harassing" killers. If your opponent is using units like fast calvary and flyers to tie your army down then get some Barbed Razordons and Salamanders to kill those things right quick. Then use Terradons to kill artillery, take out lone heroes, and harass the enemy while stopping them from marching. Saurus warrior blocks with spears are pretty effective. I suggest staying away from Kroxigors.
Is this a monetary oppinion or did you actually try to use them as a main battle force, because that's not what they're for. There is a HUUUUUUUUGE debate about what setup is better for saurus, trust me you do not want that starting up in your thread.