If you're a frugal shopper, this Forever 21 Tank will fit the bill. It's a popular choice, while not very pricey. Another good option is this Forever 21 Tank. While the price is rather reasonable, be sure that this piece will become a valuable addition to your wardrobe.
For something in the middle of the price range, look no further than this Forever 21 Crew-Neck Tee. This item doesn't cost too much, but definitely deserves a place in your wardrobe.