|"I clicked onto 'Be Frugal' for some restaurant coupons and now I have a Yahoo homepage"|
I'm sure there was a warning that your homepage would be changed but you ignored it. And I'd be willing to bet other changes were made too. Probably a special coupon printer was installed. Do you now have the Yahoo toolbar too? If you do, I suggest you uninstall everything associated with 'Be Frugal' then scan for malware & viruses.