Liberty Reserve was a digital currency and payment system that allowed users to make payments and transfer funds anonymously. It was popular among online criminals and was eventually shut down by the US government in 2013. As such, it is no longer possible to buy Liberty Reserve.
There are a number of other digital currencies and payment systems that can be used to make payments and transfer funds anonymously. Some of the most popular include Bitcoin, Litecoin, and Ethereum. These currencies can be purchased through a variety of exchanges and platforms.