Save Our Sovereign U.S.A (SOSUSA) is an immigration forum that covers a range of issues from illegal immigration to the North American Union to the trans-Texas corridor. Their focus has been around the North American Union, but since I first visited the forum they have included other areas of interest including: amnesty, open borders, the SPP, freedom of speech, the 2nd amendment, the 14th amendment, those who are selling out our country and anything else that is threatening the well being and sovereignty of these United States.
I'd recommend you head over there and check it out, even if you aren't overly concerned about the NAU, because there is a lot of good information regarding immigration in general.
Here's from their mission statement for the forums.
Secure Our Sovereign USA's mission is to educate and inform Americans about the plan to merge our United States of America into a union with Canada and Mexico. Our intention is to explain the many tools being used in the unconstitutional implementation of the North American Union, with "illegal migration and the proposed amnesties" as one of the most important instruments being used; to unite Americans to fight the North American Union and to preserve our Constitution, protect our Sovereignty and our Representative Republic. We believe in the integrity of our great nation as the founders envisioned ~ of the people, by the people, for the people.
This is our mission ~ "For The Glorious Cause of America" ~ 1776
Check It Out!