This is a question every startup blogger will be interested in knowing.Usually blogspot blogs will start to indexed when google spiders understand it to be legitimate.The correct time period for getting indexed is unpredictable but i can suggest you certain things that will certainly boost up the speed of indexing.
Task1.Write 10-20 well designed post.Desirably between 100-150 words.
Task2.Go to Google webmaster tools and submit a sitemap for you site once you are done with task1
Task3.Add your blog to Google
Task4.Start posting in social bookmarking sites like digg and del.icio.us.This will get you some exposure and your pages will get indexed by
google while those sites get indexed.
Task5.Post regularly atleast 1 post per day.
Task6.Meanwhile add your blog url to blog directories.
Task7.Last and the most important tip.Show some perseverance it won't be long when you start seeing your pages on search engines.
Hope you found this information useful.