I have this already, which takes my visitors to Google maps to find their mileage distance, but I want the mileage data to be extracted from Google and instead shown on my site alongside the "get" button as a text display without them having to leave my site to get that information.
<form action="http://maps.google.com/maps" method="get" target="_blank">
Enter your city:
<input type="text" name="saddr" />
<input type="hidden" name="daddr" value="Petersburg, Virginia" />
<input type="submit" value="get mileage" />
</form>