To reduce the amount of junk mail delivered to you contact the Mailing Preference Service Tel: 0845 703 4599.
To stop unaddressed leaflets being delivered by Royal Mail contact:
Freepost RRBT-ZBXB-TTTS, Royal Mail Door to Door Opt Outs, Kingsmead House, Oxpens Road,Oxford, OX1 1RX or email firstname.lastname@example.org
To stop unsolicited telesales calls contact the Telephone Preference Service on 0845 070 0707. It may take a while for calls to reduce. If you continue to have a problem, contact OFCOM on 020 7981 3040.
All of these services are free.