I want to create a website where people can create events related to education, entertainment, sports, regional, cultural etc. Every user will have its own page which will be publicly available. Now I want to make sure that these events are searchable by all the search engines such as Google, Bing etc, as soon as the event is created. How can I achieve this?
There is nothing special you need to do to make your website crawlable, as long as your text is in html, and not generated by javascript exclusively and can be found on an url search engines will find it.
With that said if you want to speed up the indexing process you can programmatically ping google for every new content entry you make.
eg ping google:
http://www.google.com/webmasters/sitemaps/ping?sitemap=URLOFSITEMAP.xml
to ping bing:
http://www.bing.com/webmaster/ping.aspx?siteMap=http://www.yourdomain.com/sitemap.xml
Most search engines have an option for pinging similar to this. Keep in mind that yahoo and bing use the same technology, so you only need to ping bing.
You also need to populate your XML sitemap everytime you create new content and then automatically ping it using the url above. This will make sure that all your content is indexed as fast as possible.