The errors in the first answer are mostly clarified in the second, but consult an attorney familiar with the topic.
They answers also do not answer the question ;) and that was where to find a form - and the very simple method of obtaining the document from Pacer will always work for such a need.
After a web search gives you a case number and a reference to a Motion to Reopen Bankruptcy Case, log into Pacer (http://www.pacer.uscourts.gov) or the Electronic Case Filing server for the court referred to, search for the case and court, obtain the docket report, find the Motion to Reopen, and download that document and edit it.
IRS obligations do not get discharged as the result of bankruptcy. All other creditors have to write off their debts, but the IRS gets to threaten you for the rest of your life, and even go after your estate.
Bankruptcy is a Federal Case, and the form would be the one used by the circuit in your area. Speaking to the Court Clerk should get you what they want to see.
Re-opening a closed case is not for the faint of heart or wallet. And, if it even can be done, some real cause for it better be able to be shown...the fact that you just promised the court (and everybody else) something, many times over, made agreements etc. (probably that even had references to taxes, etc) but apparently didn't think about taxes, simply may not fly.
Then, as above notes, do you really want to do so? Probably depends on the Chapter you filed and if/when you filed returns, when the IRS gave their notices and if there is a lien already: Most tax debts can't be wiped out in bankruptcy -- you'll continue to owe them at the end of a Chapter 7 case, or you'll have to repay them in full in your Chapter 13 plan.
If you need to discharge tax debts, Chapter 7 will probably be the better option -- but only if you qualify for Chapter 7 and your debts qualify for discharge.
You can discharge (wipe out) debts for federal income taxes in Chapter 7 bankruptcy only if all of the following conditions are true:
* The taxes are income taxes. Taxes other than income, such as payroll taxes or fraud penalties, can never be eliminated in bankruptcy. * You did not commit fraud or willful evasion. If you filed a fraudulent tax return or otherwise willfully attempted to evade paying taxes, such as using a false Social Security number on your tax return, bankruptcy can't help. * The debt is at least three years old. To eliminate a tax debt, the tax return must have been originally due at least three years before you filed for bankruptcy. * You filed a tax return. You must have filed a tax return for the debt you wish to discharge at least two years before filing for bankruptcy. * You pass the "240-day rule." The income tax debt must have been assessed by the IRS at least 240 days before you file your bankruptcy petition, or must not have been assessed yet. (This time limit may be extended if the IRS suspended collection activity because of an offer in compromise or a previous bankruptcy filing.)
The Effect of Federal Tax Liens
If your taxes qualify for discharge in a Chapter 7 bankruptcy case, your victory may be bittersweet. This is because prior recorded tax liens are not affected by your filing. A Chapter 7 bankruptcy will wipe out your personal obligation to pay the debt, and prevent the IRS from going after your bank account or wages, but any lien recorded before you file for bankruptcy remains. In effect, this means you'll have to pay off the lien in order to sell the property.