NYC to DC? Megabus?????

Both Megabus and Bolt Bus drop you off in a parking lot designated 10th and H streets NW, but the bus actually lets you off near the 11th Street side of the lot (10th Street actually dead-ends at H, and the parking lot entrance is on 9th). Go to the 11th Street side, walk a block and a half to G Street, and you will hit the Metro Center station, serviced by the Red, Blue, and Orange lines. If you go back toward the 9th Street side, where all traffic enters, you can walk a block and a half to the Gallery Place stop at 9th and G streets, served by the Red, Green, and Yellow lines. I think Metro Center is just a bit closer because of where the bus actually lets you off.

Metro Center and Gallery Place both have multiple entrances, and they are marked by brown pylons.

According to their website, Megabus drops off passengers at a parking lot at H and 10th Street, NW in Washington (they don't use a bus terminal, which is one reason their fares are low). The closest Metrorail (subway) station is Metro Center, which is located at G and 12th Street, NW--about a five minute walk.

Check this map, it shows where the Megabus stops in Washington DC:
http://maps.google.com/maps?hl=en&tab=wl&q=H%20St.%20NW%20and%2010th%20St.%20NW%2C%20washington%20DC

The two nearest metro stops are Metro Center (4 Blocks) and Gallery Place/Chinatown (5 Blocks).
They serve different lines, so you'll want to check the DC Metro web page at wmata.com.

You can either walk to metro center or gallery place china town. I like to walk from gallery place as its closer and if you aren't familiar with the area the more noticeable station. Gallery place station is on 7th and H nw. when you get off the bus walk towards 9th and h, walk up the street until you get to 7th. You can't miss the metro.