Erik M. Jensen (Case Western) has published Indian Gaming on Newly Acquired Lands, 47 Washburn L.J. 675 (2008).  Here is part of the Introduction:

Part I of this essay discusses some of the background of Indian gaming, including [the Indian Gaming Regulatory Act’s] history, purposes, and conceptual problems. Part II introduces some basic definitional issues, “Indian tribes” and “Indian lands,” and outlines the statutory classification of different types of gaming in IGRA. With that foundation, Part III focuses on the real subject of this essay, the extent to which newly acquired lands can qualify as “Indian lands.”