I haven't filed taxes in about 4 years due to various different reasons and I want to figure out how much I owe and for which years. How would I go about doing that if I don't have some W2s from certain employers (that either don't exist anymore or never sent them to me)? I don't remember the last year I filed but I know it's been about 4 years. I tried looking for something on the IRS website and didn't find much. I know it's not as easy as just looking under my social and telling me an amount, so I want to know the best way possible to find that information so I can start making payments. Thanks.