I used to use turbo tax, if you to the irs website and your income is low enough they will direct you to companies that will do it for free.
http://www.irs.gov/efile/article/0,,id=118986,00.html?portlet=7

The cut off is 59,000 in gross income in 2009 to get it for free. I believe turbo tax is on the list.

Now I use a CPA because we own our business. So it's to dang complicated.

it really depends on what kind of deductions you have... If you can get by with the standard deduction I would suggest doing the 1040ez directly on the IRS website.