You are the only one that has all of the necessary information that will have to be reported on your income tax return for the year in order to do the calculation for the numbers that you are looking for.
If you would like to do some estimated tax calculations you would need to go to the IRS gov web site and use the search box for 1040ES go to page 6 for the 2010 Tax Rate Schedules page 7 has the estimated tax worksheet. The tax brackets for 2010 will be on page 8 of the 1040ES.
You would add all of your gross taxable wages from the W-2 forms box 1 wages, salaries, tips, etc and any other net profit from other earnings that you have in your hand and that amount would be a added to all of all of your other
worldwide gross income total and that is the amount of income that would be used to start with to calculate your estimated taxes for the year.
You can find the estimated tax worksheet and instructions by using the below enclosed information
If you would like to do some estimated tax calculations you would need to go to the IRS gov web site and use the search box for 1040ES go to page 8 for the 2010 Tax Rate Schedules and page 7 for the worksheet.
You can try anyone of the online estimated tax calculators for some estimates to get an idea of what things may look like after using the correct IRS forms and compare the numbers.
Use your search engine and type ESTIMATED TAX CALCULATORS and you will be able to find several of them that you can use for this purpose.
Click on the below related link