My wife is a federal government retiree and has gone back as a contract employee with 1099 earnings - I am trying to find the proper form to file all the appropriate quarterly taxes and can't find the form. Please advise. Thanks!

You may be required to make estimated tax payments. The due dates are April 15, June 15, September 15 and Jan 15 (of next year). You must pay estimated tax for 2009 if both of the following apply.
1. You expect to owe at least $1,000 in tax for 2009 after subtracting your withholding and credits.
2. You expect your withholding and credits to be less than the smaller of:
*90% of the tax to be shown on your 2009 tax return, or
*100% of the tax shown on your 2008 tax return. (110% if your AGI is more than $150,000 or $75,000 for married filing separately). Your 2008 tax return must cover all 12 months.

Most of the self employed people, the easiest option is to make quarterly payments equal to one fourth of the tax for the previous year. For making estimated tax payments for the year 2009, divide your total tax for 2008 (or it may be 110% of your tax for 2008) by four and send the quarterly payments of the estimated tax using Form 1040-ES. If you use a tax software for your 2008 return, the software will automatically generate estimated tax payment vouchers with the amount filled in.
Read: Your U.S. Tax Return: Tax Filing by Self Employed Sole Proprietor or Independent Contractor (http://taxipay.blogspot.com/2008/04/tax-filing-by-self-employed-sole.html)