The RadDropDownList enables you to add RadListDataItems to it, or you can bind a custom list of objects giving a DataSource, DisplayMember and ValueMember which may be appropriate here. You might also be interested in using a RadMultiColumnComboBox which allows for multiple columns to be displayed and can be thought of as a RadGridView, in a RadDropDownList. Please have a look at the help topic here
for more information.
If none of this is quite what you meant, then please let me know some more details and I'l do my best to help