You may find the following links to equipment providers useful

Polycom

Grandstream

Linksys

The following links are friends of attend2VOIP

Attend2health - Chiropractic and healthcare

attend2IT - Make the fast moving world of IT simple

Trevor Hampton - Freelance producer / director

Modern Tennis International - Oscar Wegner’s system of coaching in the UK

MultiClinic - Crossplatform Clinic Booking System