Creating Redirection Url From Form?

I'm a non-web programmer being forced to do some web programming.

My immediate problem is that, on submission of a form, I need to be able to open a url (that I control) with the filled-in form values appended to the new url. In other words, I need to be able to do the equivalent of :

<form>
<input name="key1" type="text"/>
<input name="key2" type="text"/>
<input type="button" value="Submit" onclick="window.open('http://new.domain.com/newpage.html?key1=val1&key2=val2')"/>
</form>

I would really like to do this without server-side code.