Relationship between datacombo and label

Please help me to solve the problem.....(view the attachment)

I have a Products table containg ProductName and UnitPrice. The database is created using Access 97.

How can the UnitPrice being automatically displayed on the Label.caption while a particular product is clicked within a datacombo box?

Besides, in datacombo box, its default text should be "- Select item -" , why does the datacombo show "Digital Camera" instead of the default text? How to set to default text?

**the path to link to database of the adodc has to be changed