You could study the local dialects of that community and how they evolved, is it a bilingual community? Does it have two official languages? Or does it have one language for official correspondences and one for every day communication? Is this community affected by a foreign culture or language? Is the native language still used? If you search for these issues you will get interesting resources.

It depends very very much on what you want from your study. Is is about language variation? - so you look at the phonetical properties of the spoken utterance produced by different part of the community (either via age or socio-economic parameters) to look at differences or changes? Like, for example, younger vs. older speakers in inner and outer London: Cheshire, J., Fox, S., Kerswill, P., & Torgersen, E. (2008). Linguistic innovators: The English of adolescents in London. Final report submitted to the ESRC.

Or do you want to look at the wording (lexis) employed? Again, similar parameters. For example:Ito, R., & Tagliamonte, S. (2003). Well weird, right dodgy, very strange, really cool: Layering and recycling in English intensifiers. Language in society, 32(2), 257-279. or: Tagliamonte, S. (2005). So who? Like how? Just what?: Discourse markers in the conversations of young Canadians. Journal of Pragmatics, 37(11), 1896-1915.

Or, of course, you can look at sociolinguistics - how different communities use different markers, in effect, different variants - like the studies of Bill Labov in the US, Peter Trudgill in Britain.

There are several aspects that you may want to consider. Have/Has the language(s) of that community already been described? How much is already known about them? Here are some suggestions for different areas of research:

Some research studies that may be relevant to your study include: