google search with "site:"

[rock]

I'd like to include a search box that automatically appends "site:www.sun.com" for example to the query.

The basic code is:

      <form action="http://www.google.com/search" method=get>
        <input name=q size=40 value="">
        <input type=submit value="Search" name="submit">
      </form>

I'm pretty sure I need another input tag, and I've tried things like:

<input type="hidden" name="site:" value="www.sun.com">
 or 
<input type="hidden" name="+" value="www.sun.com">
 or
<input type="hidden" name="" value="site:www.sun.com">

but nothing has worked.

In the end, the actual URL should be for the user input of "blade":
http://www.google.com/search?q=blade+site%3Awww.sun.com

The blade query comes through fine, but whenever I add the + manually, I get a %2B instead. And it gets tacked on as another query.

Any suggestions?