Hi,
My spouse just came into US, Should I apply any ID card for her so that I use that as a proof for my tax returns. What documents I need to prepare after she comes to US for the first time.

Assuming you mean to apply for an ITIN, you will need to submit a notarized photocopy of her passport with the tax return, which she must sign as well as you.

Thanks for your response, where do I apply for it

You will file Form W7. Download from www.irs.gov and go through the instructions.
First question you have to answer, why ITIN is needed?