Buying land has been covered in detail, but not selling land.

[Henrie Ansar]

What is the process by which I can sell my land? I have found no details in the forum.

[Amethyst Jetaime]

http://community.secondlife.com/t5/English-Knowledge-Base/Selling-and-renting-land-to-others/ta-p/700135

[Lindal Kidd]

It's as easy as buying land, really.

1. Open About Land, click the Sell button. 

2.Set your asking price. 

3.Set whether you want to sell it to anyone, or to a specific person.

4. Profit! :smileywink:

Group owned land is a bit trickier.  Read Amethyst's link carefully.