Here are the appellee briefs in Warren v. United States:
Brief for Seneca Nation Amicus
Lower court materials here.
Warren v. United States
Constitutional Challenge to IGRA by Anti-Seneca Gaming Advocate Rejected
As first noted on Indianz, here are the materials in Warren v. United States (W.D. N.Y.):
Warren Proposed Amended Complaint
DCT Order Dismissing Warren Complaint
UPDATE: 01 Amicus Seneca Nation of Indians’ Response to Plaintiff’s Motion to Amend Complaint
Seneca Allowed to File Amicus in Challenge to Seneca Gaming Laws
Here is the district court order in Warren v. United States (W.D. N.Y.) — DCT Order re Seneca Amicus Motion
Turtle Talk 