Same thing happened to me. In 2013 I bought 13 litecoins from litetree and forgotten all about em. Bitcoin goes nuts and I look to see where they are and I haven't a clue. A google search turns up misery about litetree and the website doesn't exist.
I searched my email and I retrieved some which go as follows:
Trade orders have been executed
1.2 LTC at 58.0 USD per LTC for a total of 69.6 USD
5.8 LTC at 58.0 USD per LTC for a total of 336.4 USD
And that's it!
I have a pin code/validation code, 5 digits.
And I have an account ID code.
I think I'm screwed!