Almost all tourist methods leave from Ushuia, in Argentina. You could get work on a boat, book a cruise, or take a tour with GAP Adventures, among others. However, there is almost NO cheap option.
However, if you're after a cheaper option and have some time to spare, arrive in November. It's the start of the season and many of the boats aren't full. As such, they often offer 50% off the prices of trips to Antarctica. It's still expensive, but a massive saving!
November is also a good time to visit the area, with El Calafate up north being a gateway to the glaciers, mountains and national parks. Perito Moreno glacier HAS to be seen to be believed!
