Well, as I told you before, my German ancestors were from Heidelberg, so if you know about the people who historically lived in southwestern Germany, that would be a great start.
One thing you can do to figure out which Tribe or Tribes you might be descended from is to look at the history of the city, the region it's in, and the regions immediately surrounding it. You can also compare a map of modern Germany to a rough map of where the old Tribes roughly were said to be at various times. This is an area where Wikipedia is actually a pretty good place to start.
From there, you can look at various local folklores through the ages, what stories were told there, regional customs and superstitions, and compare those to the wider Germanic mythos.
When it comes to this religion and way of thinking, where so much has been lost over the years, it's up to you to do a lot of the work yourself. Heathenry is an ongoing process of discovery. It's not like other religions where other peoples' books will tell you everything what you want to know. (Incidentally, I'd be careful with the books by the Wodening brothers, since they have gotten some things VERY wrong when it comes to vocabulary.)