Further to this list production, as most data is accessible to excel or other spreadsheets, a macro script can convert the two columns to a string with the appropriate delimiters.
As this forum does not allow me to post an actual working spreadsheet. You (or any interested party) would need to PM their email address to receive an example
Sub Macro1()
Dim i As Integer, astr As String, bstr As String, total As String
For i = 0 To Selection.Rows.Count - 1
astr = ActiveCell.Offset(i, 0)
Do While InStr(1, astr, " ")
pos = InStr(1, astr, " ")
astr = Mid(astr, 1, pos - 1) & "%20" & Mid(astr, pos + 1)
Loop
bstr = ActiveCell.Offset(i, 1)
Do While InStr(1, bstr, " ")
pos = InStr(1, bstr, " ")
bstr = Mid(bstr, 1, pos - 1) & "%20" & Mid(bstr, pos + 1)
Loop
total = total & "&" & astr & "=" & bstr
Next
ActiveCell.Offset(Selection.Rows.Count, 0) = total & "&"
End Sub