Obtain a copy of IRS Form 4868 from the IRS web site, your public library, or an IRS office. At this late date, the IRS web site is yourbest bet. http://www.irs.gov.
If you are or expect to be out of the county on April 15th, you automatically have until June 15th to file your return. If you will need more time than that, file IRS Form 2350. It is always better to file for an extension. The IRS computers have a way of messing things up.
Fill out the Form 4868 or Form 2350, making sure to follow the instructions carefully. You should do your best to estimate the total amount of taxes you will have to pay. Use whatever information you have available, such as W-2s, because full payment of your taxes are due by April 15th. This is true, irrespective of whether you qualify for the automatic 2 month out of county extension, the automatic 6 month extension, or the 2350 out of country extension.
Once you have determined whether you will likely owe money to the IRS and have filled out the IRS Form 4868 completely, send it off. Mail it or use electronic filing. If you owe money, there will be one address to use. If you don’t owe any money, there will be a different address to use. The instructions to Form 4868 tell you where to mail your form and money.
Now, create a plan that will allow you to gather all the information you need to file your 2008 tax return by your extended due date.