Desperately Need Help Pleaseeeee!!!

Hey Guys,
I am new to Visual Basic and I'm finding it very difficult to learn with this confusing assignment that has been handed to me. :(

Here's what i have to do..
I have a Root Folder called 'CDS' with Bunch of subfolders of Vendor names then that would have folders of Devices. And each of these Devices have Subfolder with Serial Numbers and those folders have more subfolders with Dates on them and when u open that folder, you get bunch off files (data analysis,calculations,xml files and more..) Any of these folders can be actively added, deleted or changed. so the program needs to be able to update in real time.

To makes this easy for you to visualize.. i have uploaded a sample of how it would look in xml format ("mytest01.xml").. Note: my directories is made up of folder located in document folder this is just an example.


So my objective is to create a database application that would be make is easy to navigate through those files for comparison purpose.

Here's how the Application that i started on looks like. i have attached an image (CDS.jpg)

What i want is in Vendor Combobox to list all the Brands, and according to what i choose i want the Devices combobox to list all the devices of that brand and so on till i choose the date and thats when all the files show up in the list box.

The only thing i have gotten so far is to get all the vendor folder names in the combobox and i dont know what to do after that.. its very confusing and i cant seem to find any similar material in google. :cry:

Heres how the code looks so far in form.vb.

Code:

---

Class FormCDS

    'Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        Dim tmpDir As New IO.DirectoryInfo("Y:\CDS")
        Dim subDir As IO.DirectoryInfo
        For Each subDir In tmpDir.GetDirectories()
            ComboBox1.Items.Add(subDir.Name)
        Next
    End Sub
End Class

---

Any help, advice, or suggestion would do to help me get started. im new to vb so please dumb it down as much as possible lol

Thanks in Advance!!! :)