I called the Office of the President of the Oglala Sioux Tribe of Pine Ridge, and spoke with Ms. Fire Thunder herself. (In case you haven't seen it, this is in reference to http://www.indianz.com/News/2006/013061.asp)
If you want to mail donations to the reservation, you may do so at:
Oglala Sioux Tribe
ATTN: President Fire Thunder
P. O. Box 2070
Pine Ridge, SD 57770
OR: and this may be preferred, due to mail volume:
ATTN: PRESIDENT FIRE THUNDER
PO BOX 990
Martin, SD 57751
Enclose a letter voicing your support and explaining the purpose of the donation. Bear in mind, the Pine Ridge Res is not exactly dripping with disposeable income, so do consider donating funds directly to the tribe as well as specifically for this effort.
ETA: Make checks out to OST Planned Parenthood Cecelia Fire Thunder. This will ensure that the funds get routed properly.
For email contact, you can contact the president at:
firethunder_president AT NOSPAM yahoo DOT com
cc:vbush AT NOSPAM oglala DOT org
That is Ms. Fire Thunder's personal email address; I have received permission to post it here. For the sake of record keeping, do cc: the listed address on all correspondence; that's her official secretary.
She was frankly kind of surprised that a white girl from Seattle was calling to express support, and even more surprised that the news had spread so far so fast. She's likely to get deluged with screaming hate mail soon, so get your support in fast. Send email with good thoughts if you can't send money.
ETA: Yes, please, dear God, link it anywhere and everywhere!
ETA: OK, folks, before you all go off half-cocked, read the disclaimer. If you want to argue, do it somewhere else.