2 ways 1) type site:yourblogdomain.com into google, if you get your blog showing up, you're in! 2) Get a Google webmasters account and add your site, it will tell you if your site has not been indexed already.
If you blog isn't indexed, the quickest ways are to: 1) Use a Pinging service 2) Make a post with some popular tags (only if it is a Wordpress.com blog) 3) Bookmark it (Digg, StumbleUpon, Propeller...etc) 4) Build links into it (Blog Comments, Forums...etc) HTH
Once you are indexed you can also check on the Google toolbar by pressing the pagrank bar and selecting "cached snapshot of page" to see Google latest view of your site.