I think if you use the keypress, like example below, it will give you
what you want.

Private Sub txtAcctNum_KeyPress(ByVal KeyAscii As
MSForms.ReturnInteger)
If KeyAscii < Asc("0") Or KeyAscii > Asc("9") Then
MsgBox ("Please enter numbers only")
End If
End Sub

Or AfterUpdate might better meet your needs, see below for an
example:

Private Sub txtAcctNum_AfterUpdate()
Dim hold As Integer
If Len(txtAcctNum) > 5 Then
MsgBox ("Account Number can not exceed 5 digits")
End If
End Sub

AfterUpdate is a good idea. You can also use Change, except for it fires
with every keystroke.
In AfterUpdate you can set a flag and then check it later. You'll need to
have a change  event handler like this for every one of your textboxes. I
don't think there's a form-wide "dirty" flag.
In my apps, most of the time I don't bother comparing  against the original
value, I just record the change event happening and just assume they changed
something, even if they changed it back to the original value. But that's
me.
I've never come across something significantly easier than this.
Dave

In a recent Word front end app to an Access DB, I just let it go that if
they made any moves in any field on the form, I assumed they made some
change to the data. So I used the change  event and then set a global
variable that the data was change. That adds the word CHANGED! to the
titlebar of the dialog to draw attention so the user  knows they did
something, in case it was a mistake, but then I also asked...before they
bailed on the dlg...whether they wanted to save the changes.

This way I captured the fact that something change, but left it up to the
user to decipher if the change was something they wanted to commit to the
DB. If they clicked yes on the Q msg...it would pass the data. Otherwise it
would just continue on without saving.

Actually I'm not interested with the first question  which is about TextBox
Change or etc. But what Dave suggested as a solution is in my focus. I mean,
making records in Access DB. But i'm new in this. Please give me some simple
codes about this. And maybe some links.

Just thinking out loud really... isn't there an IsDirty property
somewhere?

I'm pretty new at this, but I do Call several sub routines any time a user
changes a cell value. I have the following code on the worksheet  (right click on
the tab name & select "View Code")

Private Sub Worksheet_Change(ByVal Target As Range)
Call Macro1
Call Macro2
End Sub

This does not fire on each keystroke, but does fire if the user  changes any a
value in any of the unlocked cells and then activates the change  by hitting
<Enter> or moving  to another cell (arrow keys, <Tab>, or mouse click).

I think there is a misunderstanding here.
Your code is fine, but it checks the cells.
The initial question  was:
"my question is, is there a way to detect  if the user  has entered/altered
values in "any" of the textboxes"

Let's say that the cells "belong" to the worksheet. So if you want to find out
a change  in the worksheet(cells), that's fine (i.e. you check the event that
belongs to the worksheet  list of events)
versus textboxes  which are controls on a userform.
In this case, you need to check other events such as David suggested (i.e.
events that belongs to the textbox  list of events).
I hope I have made it clear.

You are absolutely correct that I misunderstood the original question  :(

I appreciate you taking the time to offer such a complete explanation... My
whole purpose for monitoring this board is because of excellent and genuine
helpfulness of participants such as yourself.