make any button of your desire link on your site without having too much problem so let start the steps:-
1 go to layout and click on add gadget.
2 choose "add html" and click.
3 copy this link
<form>
<input type="BUTTON" value=" " onclick="window.location.href=' '" />
</form>
and between first blank space remove spaces and type your link title and then between second given space paste your desire link
4 click on save button and save it and see the button on your site.....
for example
<form>
<input type="BUTTON" value="type link title" onclick="window.location.href='paste link address'" />
</form>