PBS
Pbs: The New Americans
This site from PBS chronicles the miniseries coming in April of 2004 entitled "The New Americans." The site documents the new American immigrants: read stories of immigrants from Argentina, China, Mexico, Hungary, Taiwan, Russia, and more.
New York Times
New York Times: Crossword Puzzle: Immigration
Here is an interactive & printable crossword puzzle developed by the New York Times Learning Network. The theme of this puzzle is Immigration.
Other
Statue of Liberty Ellis Island Foundation: The Peopling of America Timeline
A history of immigration timeline, which discusses and illustrates periods of U.S. immigration history, pre-1790 through 2000.