Hi John,
Unfortunately there isn't the ability to upload a list of changes in a
spreadsheet directly via the API, you would need to write a program
that will parse the spreadsheet and make API calls to modify the
keywords. There are a number of client libraries available that make
it simpler to call API methods, which are listed here:
http://code.google.com/apis/adwords/docs/clients.html.
You may also want to investigate using the AdWords Editor, a free
program provided by Google that allows you to work with your AdWords
account. It supports the upload of CSV files, and this may be a
simpler way to achieve your goals. You can download it here:
http://www.google.com/intl/en/adwordseditor/.
At this time the report data can only be returned in XML format, but
thanks for letting us know about your interest in other formats.
Best,
- Eric Koleda, AdWords API Team