How do I construct an if else statement to check if a combobox value is within a certain range

I have a combobox list that is comprised of 5 ranges each from a different worksheet from a different workbook. I want to check if the combobox value is within a certain range (check to see what worksheet its in) by using an if else statement, but I can't get the code to work:

Sub TextBox2_Change()

Dim value As String
    value = ComboBox1.value

Dim bdate As String
    bdate = Format(Now(), "mm/dd/yyyy")
Dim ddate As Date

Dim Found As range
Set Found = Workbooks("Library_Database.xlsx") _
            .Worksheets("Sheet1",  "Sheet2", "Sheet3") _                                  
            .Columns("A").Find(what:=value, LookIn:=xlValues)

If Found = Workbooks("Library_Database.xlsx").Worksheets("Sheet1") _
           .Columns("A").Find(what:=value, LookIn:=xlValues) Then
    ddate = DateAdd("m", 2, bdate)
ElseIf Found = Workbooks("Library_Database.xlsx").Worksheets("Sheet2") _ 
               .Columns("A").Find(what:=value, LookIn:=xlValues) Then
    ddate = DateAdd("h", 3, bdate)
ElseIf Found = Workbooks("Library_Database.xlsx").Worksheets("Sheet3") _    
               .Columns("A").Find(what:=value, LookIn:=xlValues) Then
    ddate = DateAdd("d", 2, bdate)
End If

Msgbox "" &ddate, vbinformation

End Sub

PLEASE HELP!!!!!