Seriously, this is a terrible way to code - you will never progress anywhere useful going about things this way. This "spaghetti code" - mixing HTML with server side code - goes completely against what ASP.NET is about.
If you haven't got it, you can download free versions of Visual Studio from the Microsoft website. Learn to use it (and .NET) properly, and you'll find programming much more enjoyable and even easier too.
In your case here, you'd use a Repeater control - something like:
<pre> <HeaderTemplate><table></HeaderTemplate>
<ItemTemplate>
<tr>
<td><asp:Literal runat="server" ID="litX"></asp:Literal></td>
</tr>
</ItemTemplate>
<FooterTemplate></table></FooterTemplate>
Then in the code behind, perhaps in Page_Load or a button Click event, you have your For...Next loop
For Each one_document As Object In FileRepository.GetAllDocuments()
...
Next
and in that assign the values you want to some kind of datasource - a collection, maybe, and DataBind that to the repeater.
Finally, in the repeater's ItemDataBound event, you set the value of litX accordingly.