Applying for Green Card

Hi,

I have a question, please give me some advice if possible..

Here is the whole story in short:

I entered legally on B2 Visa and I married to a US Citizen in US in a
valid period of 6 Month. My wife has a full-time job now but the
problem is, I need the past three years of Tax Return to file in the
papers for my Green Card. She filed the taxes for the past two years
but not before that because she was a student before that. I did get
the letter from IRS as required for such case, but my wife's Tax
Returns are below $15,000.00 which shows that I will need a sponsor
for my case. Now she is earning good money this year and her taxes
forsure will pass $20,000.00 by the end of this year. Someone told me
if I get the projected Income from her work-place,that will show her
taxes for this year and it can solve my problem of sponsor, but
someone else told me, I will still need a sponsor even though I get
the projected income .
Please help me or give me your opinions on this matter, do I need a
sponsor or not? if so, is there any way I can get away from this
sponsor, I mean, is there any way I can file in papers without
bringing sponsor in this whole matter?

I will be very thankful for any sort of information about my case,

Thank you.