Please let me know how do we install Cloudera express version from now on. As I could only see only cloudera enterprise edition. If that is the only option how do I get the enterprise edition with the credentials. And what will be the cost for it.
Please help me on this.
Cloudera Express is no longer available, please see the announcement here: Cloudera Enterprise 6.3.3 Released …and scroll down to the section titled Important Note About Cloudera Express.
With regard to your other questions, "how do I get the enterprise edition with the credentials. And what will be the cost for it", you can see answers to those two questions in this recent thread: Hadoop vendors.
What @Daming Xue wrote above will be your best option if you're looking for a trial of an up-to-date Hadoop distribution.