There are several ways to help feed the Google Crawler URL.
The first way is to go here and send the URL ---> www.google.com/webmasters/tools/submit-url/
The second way is to go to Google Webmaster Tools and click "Get as GoogleBot"
And then enter the URL you want to add:
http://i.stack.imgur.com/Q3Iva.png
Then the URL will look something like this:
http: \\ example.site Web success URL sent to index 1/22/12 2:51 AM
As for how long it takes for a question to appear on google, there are many factors that can be contributed to this.
If the site owners use Google Webmaster Tools, the following setting is available:
http://i.stack.imgur.com/RqvOi.png
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