Vouchers for MSN,google, YPN ?

[positivecarry]

A few questions about these


1.Do these engines have voucher deals all the time or do they come out once every so often?
2. where do you find them( I tried searching google, but I actually got results for people selling them)?

3. What denominations do they come in?

4. If I do some comprehensive research would I be able to turn a profit with a voucher , or is it more than likely that it would be a learning experience because there is luck involved in the process?

Any responses much appreciated.Thanks.