I am happy to see the Eureka lemon seeds I planted last week are sprouting. The plant in the pot is a Kalamansi (Calamondin) that I planted from seed last November. The great thing about citrus seeds is that most of the off spring will be genetically true to the parent. There are but a few varieties in which this is not the case. Frankly, though I grow these plants from seeds because I enjoy having them in the house or on the patio. It's an inexpensive way to start plants. And if I get fruit in 8-10 years that's all bonus to me.
BTW, the lemon seeds came from a lemon we bought at the grocery store. I cut it up to go in the water at supper then planted the seeds after supper. The Kalamansi seeds were from a small bush I have growing on the patio. The point is, you can use seeds from sources already in your life. They don't require soaking or much preparation.
I mix my own potting soil but you can use a standard mix. If you can find a citrus/cactus mix, all the better. Citrus likes to dry out between waterings.
It would be fun for kids to each have their own lemon tree.