Hi,
Here are some excellent info on effective telephone techniques –
1. Non-Verbal Communication on the Telephone - http://www.directutor.com/content/non-verbal-communication-telephone
2. Using Good Telephone Etiquette - http://www.directutor.com/content/using-good-telephone-etiquette
3. Cell Phone Manners - http://www.directutor.com/content/cell-phone-manners
4. Effective Use of Conference Calls - http://www.directutor.com/content/effective-use-conference-calls
5. Using Voicemail Effectively - http://www.directutor.com/content/using-voicemail-effectively
Regards,