Currently the best way to buy Litecoins is to trade them for Bitcoins on an exchange market. The main Litecoin exchange is Btc-e. You’ll want to first buy your Bitcoins either locally or on a reputable exchange website.

Step-by-step instructions to buying Bitcoins and exchanging them for Litecoins:

This guide only applies to the USA; these services below only work for US residents.

1) Buy Bitcoins locally or transfer money to MtGox using Dwolla. MtGox also supports other services for moving money from your bank account to the exchange:

Services supported by MtGox

2) Use BitInstant to transfer from MtGox to Btc-e using the MtGox coupon code to Bitcoin address method:

MtGox Coupon to Bitcoin

The address to deposit to can be found on the “Add Funds” page on Btc-e after clicking the “Make a deposit” button for BTC.

3) Now you can convert to LTC by selling Bitcoin and buying Litecoin.