The Globe and Mail has a graphic/map of New Orleans, showing areas of the city that are below sea level and “well below” sea level (nothing more refined than that). The Washington Post has a colour map/graphic showing similar information. Neither shows the extent of flooding.

USGS Landsat has a satellite image of the flooded areas, some it under cloud cover (by way of The Map Room). Orbimage has a couple of before and after satellite images but it is of a very limited area around the Louisiana Superdome.