W-2s are mailed by January 31.  Some employers make their W-2s available online, and some employers make their W-2s available as direct import into Turbotax. 

Check with your employer.  If you don't have online access or access through turbotax, you might be able to have a friend forward your mail to you.

Otherwise, at the beginning of April, if you are unable to prepare your tax return, you can file a request for an automatic extension that extends the filing deadline to October 15.  This does not extend the deadline to pay by April 15 if you owe, so you will need to prepare an estimate and pay taxes if it looks like you owe them.  When you submit your actual return by the new deadline, if you overpaid your estimate, you will get a refund.  If you expect a refund, you do not have to pay tax with the request for extension.