Retrieving a list, by iterating through a list
You're looking for the LINQ-equivalent of an IN clause in SQL. So something like this:

SELECT value FROM tblEquipment_Attributes 
WHERE Category_Attribute_Identifier IN (&lt;list of integers&gt;) 
AND Unique_Item_ID = itemID;


So what you could do is write your LINQ statement to see if the Category_Attribute_Identifier is in the list. Then your function will look something like this:

Function getValues(catAttIDs As List(Of Integer), itemID As Integer) As List(Of String)
    Dim db As New Model1

    Dim currentValues as List(Of String) = (From row In db.tblEquipment_Attributes
                     Where catAttIDs.Contains(row.Category_Attribute_Identifier) _
                     And row.Unique_Item_ID = itemID
                     Select row.Value).ToList()

    Return currentValues
End Function


Note that ToList will create a List&lt;T&gt;, where T is the type of the elements. As long as Value in your db is a varchar, it'll be a List.