How can I add company name to drop markers in Google Maps

I bought Google maps specifically to add company names to each marker - I can only add addresses. Address without company names is not useful for my client - any way to add a title/company name to each marker.
Or any other plugin that will allow me to add a name to the address?

Here's my link
http://www.gmedc.com/gm/maps/

thanks,
Chris Demers