Cathy, here is a recipe for the sour cream black walnut cake, from Cooks.com:
SOUR CREAM BLACK WALNUT CAKE 2 sticks butter
3 c. sugar
5 eggs
3 c. sifted flour
1/4 tsp. baking soda
1 c. sour cream
1 tsp. vanilla
1 c. crushed black walnuts
Cream butter and sugar and cream well. Add 1 egg at a time and beat well after each. Alternate flour and sour cream beating after each addition. Add vanilla and black walnuts. Bake in tube pan for 1 hour 15 minutes at 325 degrees. Cool before removing from pan.