Here's what you need to do:
1. If you want to include your wife in your tax return, then you should fill out form W7 and have your wife sign it. In order for IRS to process this form to issue an ITIN, you should submit notarized copies of your wife's passport to establish foreign status. You can either have your wife send her passport to you and get notarized here or have her go to a local US Consulate and get it notarized. There is a $30 fee associated with it if you take the latter route.
2. Second, you and your wife should sign a letter stating that she wishes to be treated as a resident for US tax purposes although she was a nonresident. Refer to pub 509 for more information on how a nonresident spouse can elect to be treated as a resident. If your wife had any income in the year 2003, then you will be taxed on your combined worldwide income. If your wife had little or no income, then there is nothing much to worry about.
3. Complete form 1040 and send it along with the form W-7 and supporting documents to the address mentioned on the instruction packet of form W-7. Please note that you should not send it to the regular IRS address.
Finally, the tax accountant I consulted told me that I could file the tax as a single person now and perhaps, if need be, file an amended return once my wife arrives here and obtains an SSN. Alternately, I could file for an extension -- apparently, we have until October to file the tax returns without penalty but we have to keep filing extensions to borrow time.