Filling Combobox Based on another combobox.text value.

Ive changed it workbook a little to help explain.
Currently Combobox1 does not remove duplacate's Though i would like to be able to have that option If i choose.

If the users selects excelforum.com and tabs out of the combobox.
Combobox2 list is then populated with the adjacent cell for excelforum.com.

Cheers.