chewy - 10:21 pm on Aug 29, 2011 (gmt 0)
get a cheap vonage (or other) toll-free number.
forward it to any of the regular numbers
observe the telephone bill to count calls.
devise a real "conversion" type page - ideally with a special offer "fill out this form for your free consultation" or whatever.
set up thank you page as a conversion goal
track in Google Analytics and or Adwords.
Pls let us know how it works out.