As an adoptee, I think its wonderful that you are wanting to provide a home for a child. There are so many children out there who need homes.
However, as a Native American woman who practices law in the area of Indian children, I would caution you in your desire to adopt a Native American boy. As some of the previous readers have noted, there is a federal law called the Indian Child Welfare Act (ICWA). Under that act, there are specific placement preferences that must be followed in regard to Indian children. If you are a non-Native individual, you do not fall within the preferences unless you can argue a legally recognized reason. In addition to ICWA, Minnesota law also reinforces ICWA and actually provides even more protections. As some of the other Moms have noted, there is a long history of Indian children being taken from their homes and their Tribes, so the Federal Government enacted the ICWA. Unfortunately, as someone who witnesses it every day, I can tell you that Indian children continue to be removed from their families and Tribes. As a result, Tribes are willing to enforce the law in regards to their children.
I'm not sure what your rationale is behind wanting to adopt a Native American boy. But you decide to proceed, you will definately need an attorney, well-versed in the ICWA and Minnesota law in regard to Indian child adoptions. Otherwise, as one of the other mothers wrote, if the adoption is done wrong, the tribe (and birth parents) can have the adoption erased and you could lose the child.
Good luck.