Hoople - 1:56 pm on Dec 5, 2011 (gmt 0)
Adding your website to Google Webmaster Tools and thereby submitting a sitemap has accelerated the process many times for me.
Alternately if GWT isn't agreeable to you a sitemap ping could be done. Another choice is to submit the URL via Google's public new URL submit page. Sitemap ping in my experience is the faster of the two.
I usually put up a temporary link to new sites I build on one of my existing (known to be crawled by Google) sites to aid this as well.