Here are some ethnographic articles that might help orient you to the kind of material you are looking for. You could also use these along with other ethnographic sources on the culture being studied, for your paper.
Budgeon, Shelley
2008 "Couple Culture and the Production of Singleness." Sexualities 11(3): 301- 325. (really more qualitative sociology than ethnography, but I would let it pass.)
Brandes, Stanley H.
1976 "'La Solteria,' or Why People Remain Single in Rural Spain." Journal of Anthropological Research, 32(3): 205-233.
Huseby-Darvas, Eva
1987 "Elderly Women in a Hungarian Village: Childlessness, generativity and social control." Journal of Cross-Cultural Gerontology. 2(1): 15-42.
Masur, Jenny
1984 "Women's Work in Rural Andalusia." Ethnology, 23(1): 25-38. (a couple of important references to unmarried people.)