GQC,
Are you talking about 'carbonised paper' where you write on one sheet and the imprint from your ball-point pen makes the same 'mark' onto the bottom sheet of paper underneath the first?
You can buy this from any WH Smiths.
You'll need a clip board (summit 'ard) and two print outs of your terms and conditions and just slip the carbon paper, the right way round, between the sheets of paper.
Job done!