Editing Text with forms

I have to columns on a worksheet, one with a ref number and one with text information. There is a lot of data on this sheet so I am trying to put in a form with a Combo box and a text box. The idea is that you select the ref number from the combo box and then the text box is autmatically populated with the information from the second column. You can then edit the text from the text in the form and then click a button to save the amended text back into the worksheet next to the correct ref number. I have used a dynamic range to enable selection of the ref number but I am having trouble linking a text box with the data on my worksheet. Any help would be much appreciated.
Regards
Dave