In general you would find the layer (using string). Set a query filter (none or have a whereclause). Get FeatureDataTable or dataRecord. Then you can use FindField(using string). Once you find the field (column/column's index position) You must read the datatable in order to get or set values for that field.
This is just a really rough outline on how to do things.
If you don't find enough material on that link I gave you, I can certainly help you with code, mind you i'm using Mobile 10, but it should be relatively similar.
