It is very useful if you have a lot of time to commit to learning the tool, or you already have a lot of experience using it. Otherwise, if you should get the certification and do not use the tool, most of what you learned will be lost.
Success is the ability to go from one failure to another with no loss of enthusiasm.
~ Winston Churchill ~
The official website for QTP certification is www.hp.com where you can find all the exam resources and registration help of this certification.And its cost may vary depending upon your regional currency but average cost is USD $750.