There were about 120,000 Japanese-Americans in CONUS, and all but 10,000 or so who lived East of the Mississippi River, were locked up. During the progress of the war many people were released if they could relocate elsewhere than the Exclusion Zones. For example, one group were released to New Jersey to work for Birds Eye (the frozen food folks). After the war they stayed in the area and developed their own competing frozen food business.
Other Japanese-Americans managed to work at Fort Snelling and formed the intelligence operation that worked with US military forces in the Pacific.
150,000 Japanese-Americans living in Hawaii were UNTOUCHED ~ maybe 1200 to 1800 were locked up due to some claim of involvement in japanese politics.
Regarding other use of the Enemy Aliens Act, it's been pretty minimal ~ just the usual locking up of the embassy staff and business people here and there.
In fact, it's been more the case that it's NOT enforced than that it is enforced in error. When Afghanistan attacked the USA on 9/11 (yup, it happened AFTER Mullah Omar married off a daughter to Osama Bin Laden to seal the bargain that made AlQaida into Afghanistan's national army), the 25,000 Afghanis who lived in Northern Virginia were NOT rounded up. I doubt anyone even thought to do that, although there was talk of rounding up all the Saudis because so many of the hijackers in the planes were Saudi.
When we had to go into Kuwait to liberate that country from Saddam Hussein, we didn't round up the Palestinians ~ about half a million of them worked in that country at the time. They didn't even round up Jordanian embassy personnel and their families ~ I watched day after day to see if that was going to happen and all that went on was the Fairfax Police posted a patrol car outside one house 24/7 to protect the family living there from stray Kuwaities who came down from New York.
I do know Joe Dimaggio's dad had his fishing boat seized fm Fisherman's Wharf.
BTW I had no idea there was still such a thing as an Enemy Aliens Act still in effect.