If you're looking to extrapolate a random field value from a table then use the same principle like:
Randomize
Dim lngSearchNum As Long
Dim i As Integer
Dim MyDb As Database
Dim rstMyTable As Recordset
Set MyDb = CurrentDb()
Set rstMyTable = MyDb.OpenRecordset("TableName")
lngSearchNum = Int((rstMyTable.RecordCount - 1 + 1) * Rnd + 1) - 1
With rstMyTable
.MoveLast
.MoveFirst
.Move (lngSearchNum)
End With
Me!DestinationField = rstMyTable("FieldName")
MyDb.Close
Set rstMyTable = Nothing
Set MyDb = Nothing
worked on my PC anyway, however as I recall there is a problem with generating random numbers in Access so this may not be entirely reliable - sorry I can;t be more specific, maybe others knwo more.
Ian