checking for customers already in database

[#1]

We need each sales rep, whose Companys and Contacts are set at Limited Access, to be able to enter a Company name to see if someone else is already working them.  If there is a match, we would like the company name and the sales rep working it to come back in a note to the person making the request.  We understand that it is possible for a company to have multiple contacts, and therefore multiple sales reps.  We would like our reps to have the system tell them if someone is already working a particular company.  We may choose to change the rep, but we want to avoid duplicate efforts trying to contact the same company.  Currently, they have to all come to me and ask if a company is being covered - since I am the administer and have rights to all data in the system.  This is an important request for us.  Please let me know your thoughts.  thanks,

[#2]

An interesting situation I've come accross myself on more than one occasion.