The letter is in the mail, and a few months after that so will the check. The Internal Revenue Service says letters will go out starting the first week in March reminding 130 million households to file their 2007 tax returns in order to receive their share of the 2008 economic stimulus package. The one-time stimulus payment of up to $600, $1,200 if you are married filing jointly, will start in May. There also is a $300 per child payment for qualifying children younger than 17. To find out more information log onto irs.gov