看看古书未必没有裨益：http://ctext.org/fang-yan/zh

《方言》
[西漢 (公元前206年 - 9年)] 楊雄著
[又名：《輶軒使者絕代語釋別國方言》]

从维基百科抄来的英文书单：
Further reading
##Petyt, K. M. (1980). The Study of Dialect: An Introduction to Dialectology. The language library. London: A. Deutsch.
##Stankiewicz, Edward (1957), "On discreteness and continuity in structural dialectology", Word 13 (1): 44–59
##Thomas, Alan R. (1967), "Generative phonology in dialectology", Transactions of the Philological Society 66 (1): 179–203, doi:10.1111/j.1467-968X.1967.tb00343.x
##Troike, Rudolph (1970), James, E., ed., Receptive competence, productive competence, and performance., Georgetown University Monograph Series on Languages and Linguistics 22, pp. 63–74
##Weinreich, Uriel (1954). "Is a structural dialectology possible?". Word 10: 388–400.

liumx2000：从维基百科抄来的英文书单：
Further reading
##Petyt, K. M. (1980). The Study of Dialect: An Introduction to Dialectology. The language...回到原帖

这书单的资料恐怕没机会阅读得到吧