Many well known ISP (internet service providers) do not find it marketable to expand service on reservations or remote rural areas. Often, it is in a community's best interest to set up their own ISP. An ISP provides technology, software, infrastructure, and services within their tribe's geographical area. There are many ways to connect members to the internet. For example, there are wireless, satellite, and cable options.
For a series of videos on setting up a wireless network, click here.
Here is an article that can help with the beginning stages.
Here is a great example of building your own ISP:
Click here for How to Become an ISP Provider By Shari Parsons Miller.
Here are some suppliers: