Didn't come with earphones, what should i do?

Go to the Apple store or where you purchased it and see if they will provide a set of earbuds. After a couple weeks they may not do so but it is worth a try.

it depends when you got it was the box sealed

If your iPod Touch was new it should have come with some. If it wasn't new then it came as it came. Earbuds are as cheap or expensive as you have them be (depends on what you want and what you're willing to pay)

If you got this item new from the Apple store online or a retail store, you should either call Apple(800-692-7753) or visit a retail store. I'm not sure how you would prove that it didn't come with them, but its worth a try.