Ok, So your event handler for a button click will look something like this:
Private Sub oBtn_Click(sender As System.Object, e As System.EventArgs)
You can use this event handler for all your dynamically created buttons by testing for each button, like so:
If typeof(sender) Is Button Then
Dim thisButton As Button = DirectCast(sender, Button)
If thisButton.Name = "the name your looking for" then
While your enumerating all the controls on your form, you can look for your text boxes the same way. Test for a text box the way I did for a button above, and then check it's name once you cast it to a local textbox control. When you find the name your looking for, copy it's text to the listbox your want. If you are creating multiple text boxes, name them something like abtxt1, abtxt2, ect - and then test for substrings of the names. When you find an "abtxt" text box, then you know you've found one who's value you want to write to the list box...
Hope this helps.
Oh, And I HAVE to say this - you should be using descriptive names and camel case. Readability is everything. Don't be afraid to use long names for your objects... instead of abtxt, you should be using something like aboutThisUserTextBox. This way when you come back to this code next year, or even longer you will be able to read it easily and understand what you were doing. If you ever find yourself working with a team, they will thank you for it.