The most important local contacts will be the owners, or tenants, of the land. So, discover who owns or leases the land over which the researcher must go.
This is important for two reasons –
One, it is a matter of simple politeness to obtain the permission of the landowner and/or tenant. Fieldwork wil be made a lot easier if you can map out areas of individual farms and properties so that you always know who to contact.
Two, farmers often know their land in great detail and can provide useful information. This is especially so for land that was previously ploughed and then allowed to return to grassland.
Getting to know the farmer and their land usage can also be helpful in planning when to visit certain areas, e.g. shortly after ploughing, etc.
Local inhabitants can often provide background information for the area… although much of it may need to be taken with a pinch of salt!
There are sometimes local ‘collections’ of archaeological material which have never been recorded, but which still need to be taken into account.