Searching Custom Field (Linking ??)

I don’t know how to ask this questions. This is what I would like to do.

I have custom field for listings that has listor choose neighborhood/s ( like cities) to list in.

I was able to create a search that if they type in the name of the neighborhood, all the listings come up but it would be nice to have all neighborhoods listed as a choice just like choosing a category.

I can have a taxonomy list but it doesn’t link to custom field. Is there another way to add a field to listing that would connect to taxonomy???

Is there a way to have these listed like the categories are listed, so someone can click a neighborhood and see all the listings from that one area?

Any help or suggestions appreciated.
John