They have posted copies of the 2013 tax returns for the Obamas and Bidens on the White House website.
Here are the download links for the pdf files.
I took a quick glance through the returns.
Obama had to pay $1,753 for the new ObamaCare tax on investments (Form 8959).
Biden only had to pay $230 for this new tax. Biden received $30,552 of Social Security benefits last year, as he entertained the country with his crazy antics.