Where are you searching??? What states and what are the names of your relatives? The very first thing you need to do is check the names against the 1870 census (this is the first listing of Blacks after the Civil War) Once you find them, you can check slave schedules for 1860 to see if any of the ages match the listing. The only problem is that most ex-slaves did not keep the last name of their prior owners...although some did. In my case, my relatives did keep the last name which made the searching a little easier.
Now about finding your Cherokee lineage...that may be more difficult. The Dawes listing is the only official listing for Native Americans. All Natives must be listed on that list...especially those who live or lived on the reservations. This part of your search will probably prove to be a little more difficult.
If I can be of any further help. feel free to contact me.