Did you sign up for Blackberry Internet Service (BIS) or Blackberry Enterprise Service (BES). For a small business, BIS is the way to go. If you can access your email through the web, using outlook exchange website (
www.companyname.com/exchange), BIS will work. You can configure it on the handset or throught your carrier's BIS website.
BES means you have to host a BES server, not a good option for a small busness.