It will be pretty time consuming searching an entire drive. I create getFileList to recursively search all folders and subfolders returning the file paths in an array. You could speed up the process by having the function exit when it finds the correct directory.
I recommend saving the path to the registry using SaveSetting and later retriving it using GetAllSettings
The HowTo_GetFileList macro shows you how you can filter the array of file paths.

Sub HowTo_GetFileList()
Const MATCHVALUE As String = "Demo"
Dim f, FileList, FilteredList
FileList = getFileList("C:\Users\Owner\Downloads")
FilteredList = Filter(FileList, MATCHVALUE)
For Each f In FilteredList
'Do Something
Next
End Sub
Function getFileList(localRoot As String, Optional fld, Optional ftpArray)
Dim fso, f, baseFolder, subFolder, ftpFile, i
Set fso = CreateObject("Scripting.Filesystemobject")
If IsMissing(fld) Then
Set baseFolder = fso.GetFolder(localRoot)
Else
Set baseFolder = fld
End If
For Each f In baseFolder.Files
If IsMissing(ftpArray) Then
ReDim ftpArray(0)
Else
i = UBound(ftpArray) + 1
ReDim Preserve ftpArray(i)
End If
ftpArray(i) = f.Path
Next
For Each subFolder In baseFolder.SubFolders
getFileList localRoot, subFolder, ftpArray
Next
getFileList = ftpArray
End Function
The most efficient option would be to make a LDAP query to return a list of shared folders. This Sample Script from VBSEditor.com will do just that. This will require a fair amount of knowledge of your Active Directory.