This question seems can't be easily answered immediately. Because it really depends how and how often you promote your website or blog.
In google's case, they say that they crawl websites and blogs quickly. But they don't promise that your site will be index immediately. Google really rely indexing sites through quality links that links to your blog or website. So the more links to your site the more chance your blog will be on the front page of google search engine.
What to do after creating your blog?
Creating a blog is very easy and some offer it for free like blogger or blogspot blogging platform. After creating your blog,building traffic to your site isn't that easy to do. You to do some Search Engine Optimization to gain free traffic to your site.
But before you do that, create a quality contents on your blog first before you do your promotion strategy. It is funny doing promotion when their is nothing inside on your page. Don't launch your site if it is not ready yet.
After your blog is ready, launch it and submit your blog to different directories to let other webmasters and bloggers know your site. Also try to submit your site to google itself at http://google.com/addurl.html. Or you can use the google features to optimized your site. Try to visit http://google.com/webmasters and familiarized the operation of their google webmaster console.
The other thing is that create a sitemap of your blog and submit it to google and google will simply crawl your blog in days not in months
The other thing is that create a sitemap of your blog and submit it to google and google will simply crawl your blog in days not in months
Please see the video below:
