I've had good luck with ATK recipes. This one is from Cook's Illustrated (same people):
http://www.cooksillustrated.com/recipes/login.asp?docid=5456&extcode=M**ASCA00

It's for oven poached salmon. I don't have a membership, so that how you access the content, but I bet if you googled you could find it.

I've also had good luck on epicurious. You can read the reviews so that's helpful as to what works.

would like to make some for Passover-but have never poached a fish. I need a simple but flavorful recipe..lots of dill and lemon flavor TIA