I assume you mean the Shared File module.

If you view the source of the page you will see those "links" are atually buttons styled as links, they render as <input type="submit" class="buttonlink"

so you can style them by modifying the .buttonlink class which I think should be in styletext.css file.

Note that the reason we use <asp:Button is because they work even with javascript disabled whereas <asp:LinkButton does not.

Hope it helps,

Joe