Google also knows about the poor economic times which has really effect probably every business sector. Search engine marketing is also related with making business / getting more sales from the internet users / online visitors.
That's how Google want to help everybody and has recently announced the publication of the Top AdWords Tactics for Tough Times document to make things easier.
The important points which has been placed -
* Focus your ads on low prices and savings.
* Use value-related keywords.
* Make sure your ad groups are targeted and relevant.
* Don't waste money on irrelevant clicks.
* Make it easy for customers to buy.
* Focus your money on your high-performers.
Get the full details here - http://www.google.com/adwords/tactics2008/