Well you can no longer "match" because that implies participation in a formal procedure like the NRMP.
However, you can still get a residency position although most unfilled after the match will be so by now. Yet, as the start of the year gets closer, people change their minds, break contracts, etc. and spots open up, continuing on through the year. Trouble is there is no centralized database where you can find out about these spots - you have to look on specialty websites, ask around, etc. and find the spot yourself.
Best of luck...