ASP.NET (VB.NET 4.5) Calling Async WCF Method - vb.net

Question

I have been reading for days, and I can't quite figure out what I am supposed to do here. I am actually a C# developer and programming in VB.NET can be a little confusing at times. That aside, I am trying to implement Async calls from a WCF in a new project that I am creating here. I've tried it a few different ways with results, but I want to make sure what I am doing is proper.
From what I have read, you should never return a void in an async method, so I am trying my hardest to avoid it. All of that aside, I guess I just want to know if this is a valid way to go about building this page. It will be calling more than one method from the WCF as I build it out.
Public Class _DefaultReservation
Inherits System.Web.UI.Page
Dim wcfReservation As WCFReservation.WDReservationClient
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
SetupPage()
End Sub
Private Async Sub SetupPage()
wcfReservation = DirectCast(Master, LoggedInMaster).wcfReservation
Dim resData As String = Await wcfReservation.GetDataAsync(123)
Response.Write(resData)
End Sub
End Class
I guess what is confusing is if I put that code inside of an async function and return the task, I would have to mark the page_load handler as async as well. It doesn't seem right doing it this way? By doing that it seems like an async function is calling an async function. But the way I am doing it here, my async function returns void, and that is supposed to be avoided. I can post an example of the other way too if needed. Thank you!!
Edit: Does this work better?
Imports System.Threading.Tasks
Public Class _DefaultReservation
Inherits System.Web.UI.Page
Dim wcfReservation As WCFReservation.WDReservationClient
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
SetupPage()
End Sub
Private Async Sub SetupPage()
wcfReservation = DirectCast(Master, LoggedInMaster).wcfReservation
Dim getDataResult = Await GetDataAsync()
Response.Write(getDataResult)
End Sub
Private Function GetDataAsync() As Task(Of String)
Return wcfReservation.GetDataAsync(123)
End Function
End Class
EDIT 3:
Imports System.Threading.Tasks
Public Class _DefaultReservation
Inherits System.Web.UI.Page
Dim wcfReservation As WCFReservation.WDReservationClient
Protected Async Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
wcfReservation = DirectCast(Master, LoggedInMaster).wcfReservation
Dim result As String = Await wcfReservation.GetDataAsync(1234)
Response.Write(result)
End Sub
End Class

Answer 1

It is true you should avoid async void. The exception for this guideline is when you have async event handlers.
Such as Page_Load.
For more information about this guideline, see my MSDN article on Best Practices in Asynchronous Programming.
It doesn't seem right doing it this way? By doing that it seems like an async function is calling an async function.
That's perfectly correct. Async code will "grow" through your code base. The correct solution is to make SetupPage a Task-returning function and await it in Page_Load (which is an async void/Sub).
Edit:
Imports System.Threading.Tasks
Public Class _DefaultReservation Inherits System.Web.UI.Page
Dim wcfReservation As WCFReservation.WDReservationClient
Protected Async Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Dim getDataResult = Await GetDataAsync()
Response.Write(getDataResult)
End Sub
Public Function GetDataAsync() As Task(Of String)
wcfReservation = DirectCast(Master, LoggedInMaster).wcfReservation
Return wcfReservation.GetDataAsync(123)
End Function
End Class

Answer 2

As luck would have it, I just posted about Async Sub yesterday. Long story short, in your case if you use Async Sub, control will revert to the calling method as soon as the await is encountered. As a result, your page_Load handler will end before the SetupPage is complete. If you want to have Page_Load wait until SetupPage has asynchronously completed, you need to change the SetupPage to be a function returning Task and then Await SetupPage in Page_Load (causing Page_Load) to be Async.
Async Sub is valid on event handlers. Lucian discusses this at some length in his recent Async Patterns post. You may also want to check out the Async talk from ASP.Net Conf last year for special considerations on using Async with ASP.Net/WCF.