Create a Sitemap in xml format (or plain text, with one URL per line) and notify Google:

https://www.google.com/webmasters/sitemaps/stats
Sitemap Generator
By placing a Sitemap-formatted file on your webserver, you enable our crawlers to find out what pages are present and which have recently changed, and to crawl your site accordingly.
https://www.google.com/webmasters/si.../en/about.html
http://googleblog.blogspot.com/2005/...-friendly.html