Is there any way by which we can download the keywords Account/Campaign/Ad group Wise in a Single go?
Yes, there is. You can do this through Adwords editor or by generating a report and downloading it to a XL file.
Yes you can do that... eaither download the Adwrods editor here : http://services.google.com/adwordseditor/ Or you must have your own API application o do it for you... I have my own. Tim
API's are basically for large advertisers(10k keywords and more). You will have to hire some programmers to use API's. However once implemented, you can have some great information from it. You can virtually generate any kind of reports with adwords API. Also, API work on a quota system, that means more the budget, more you can use API for free, else you have to pay.