http://www.developerdrive.com/2012/08/add-a-simple-google-yahoo-or-bing-search-box-to-your-website/
Google Search Box with Radio Buttons
The above search box only allows for locating content within the designated website. However, some site owners might want to give visitors the option of looking for a keyword on the wider web, as well.
In that case, the simplest solution is to provide a search box with two radio buttons; one for the web, and the other for the site, as shown below:
The coding for the search box is as follows:
<form method="get" action="http://www.google.com/search">
<div style="border:1px solid black;padding:4px;width:20em;">
<table border="0" align="center" cellpadding="0">
<tr><td>
<input type="text" name="q" size="25"
maxlength="255" value="" />
<input type="submit" value="Google Search" /></td></tr>
<tr><td align="center" style="font-size:75%">
<input type="radio" name="sitesearch" value="" />The Web
<input type="radio" name="sitesearch"
value="yoursite.com" checked /> Only Your Site<br />
</td></tr></table>
</div>
</form>
As in the previous example, just change “yoursite.com” to the correct domain name, and the search box will be ready to perform. Note that the option to search within your site is selected by default.
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Add the code to a html box on your site.
