I know this is an old thread, but I regestered just to post this.
If you got Lemon G, it had to have come from Cincinnati or Columbus Ohio. It is a protected strain available by clone only, and the people who hold it are stingy about giving it away.
It's history is actually an old Columbian strain from a import in the 1970's, I was fortunate enough to grow this strain.
It takes 9-11 weeks flowering, and creates huge fluffy monster buds. The calyxes actually branch out so far that it's not dense at all. If a normal but that weighed 10 grams was next to 10 grams of Lemon G, the Lemon would look like a heavy ounce.
The closest relative I've found in seed form is reeferman's love potion #1. -It's also from a columbian strain.
Lemon G isn't the best yielder, because of it's fluffy nature, and the high is extremely relaxing, you can't do anything after smoking it but sit around for a while.
I know about everyone who grows it, and there isn't much chance of it hitting mainstream.
Trainwreck is a different strain entirely, it's not related to any haze plant, and you probably will never see any lemon g again, consider yourself one of the proud few who actually experienced lemon g, unless it came from athens ohio, because that particular grower sucks.
If you're in ohio, look for sensi star, silver pearl, white rhino, trainwreck and dumpster sometimes up near cleveland.
Hope this helped.