And this tool from the good people at Climate Central (h/t David Atkins over at Hullabullo) will let you see just how deep the trouble will be.
By using the slider you can control the depth of the water. The tool will then tell you how much of the state in question will be "under water" with that level of sea rise. The tool also gives you an estimate of which year (ending in zero) that a rise of that level can be expected.
For example, a +5 foot rise in sea levels and storm surge covers this percentage of the state of Florida:
Things below +5ft in Florida
Population 3,054,422 16.2%
Homes 1,603,260 17.8%
Acres 2,343,796 6.8%
For Texas:
Things below +5ft in Texas
Population 135,754 0.5%
Homes 80,738 0.8%
Acres 854,754 0.5%
For California:
California
Population 440,229 1.2%
Homes 187,413 1.4%
Acres 555,975 0.6%