Gaeas Cradle sees play in Legacy in Elves and is arguably the best land in Commander
A less obnoxious move is to use a card like Nissa, Who Shakes the World to animate a bunch of lands to mount a go-wide attack or using the Liquimetal to make a creature into an artifact at instant speed to take advantage of Tempered Steel
If it has enough counters on it, not only does it have a lot of power/toughness, but it will have Flying and Indestructible too
(Whenever this creature attacks, create X tapped and attacking 1/1 red Warrior creature tokens
This will likely make it so that one of the lands will be the same color as your commander's identity, which tends to be more useful than any color, and it is one of the best lands that allows for easy mana fixing in any deck
Trading Events: Keep an eye out for local trading events or conventions where collectors gather to trade and sell cards