Try using IGridTable, ICursor, IRow.  This code snippet is for updating raster cell values, however it shows the basics of iterating:

[How can I add a new field in a raster attribute table and loop through it?][1]

    Public Sub CalculateArea(raster As IRaster, areaField As String)
        Dim bandCol As IRasterBandCollection
        Dim band As IRasterBand
    
        Set bandCol = raster
        Set band = bandCol.Item(0)
    
        Dim hasTable As Boolean
        band.hasTable hasTable
        If (hasTable = False) Then
            Exit Sub
        End If    
    
        If (AddVatField(raster, areaField, esriFieldTypeDouble, 38) = True) Then
            ' calculate cell size
            Dim rstProps As IRasterProps
            Set rstProps = raster
    
            Dim pnt As IPnt
            Set pnt = rstProps.MeanCellSize
    
            Dim cellSize As Double
            cellSize = (pnt.X + pnt.Y) / 2#
    
            ' get fields index
            Dim attTable As ITable
            Set attTable = band.AttributeTable
    
            Dim idxArea As Long, idxCount As Long
            idxArea = attTable.FindField(areaField)
            idxCount = attTable.FindField("COUNT")
    
            ' using update cursor
            Dim gridTableOp As IGridTableOp
            Set gridTableOp = New gridTableOp
    
            Dim cellCount As Long, cellArea As Double
    
            Dim updateCursor As ICursor, updateRow As IRow
            Set updateCursor = gridTableOp.Update(band.RasterDataset, Nothing, False)
            Set updateRow = updateCursor.NextRow()
            Do Until updateRow Is Nothing
                cellCount = CLng(updateRow.Value(idxCount))
                cellArea = cellCount * (cellSize * cellSize)
    
                updateRow.Value(idxArea) = cellArea
                updateCursor.updateRow updateRow
    
                Set updateRow = updateCursor.NextRow()
            Loop
    
        End If
    End Sub

Once you are curosing the table you can get the specific field row value by using `row.get_Value(yourfieldIndex)`.  If you google 

> arcobjects row.get_Value

 you should be able to get plenty of examples showing this.

Hope that helps.
  [1]: http://gis.stackexchange.com/questions/17075/how-can-i-add-a-new-field-in-a-raster-attribute-table-and-loop-through-it