mattia - 6:38 pm on Oct 24, 2011 (gmt 0)

Common best practices says:
yes you can contact them

BUT
Do not contact them via phone, preferably use email
and
just send ONE email! DO not insist/harass

Just one email is usually ok, repeat emails will most likely upset that potential customer who might refer you to the BBB or talk bad about you in forums....

best,
Marc