There are a number of other websites that maintain data for analytical purposes. One of them is
Apart from this website, every government department in the US maintains its data. So i suggest looking up at different government websites in the US to get free data sets.
another one is (though i have not used this yet)
You can also look up for the human genomics data…There is huge data available for free, or google books data or wikidata dumps etc etc.
Hope this helps