They're pretty simple, and I doubt you'll get 1k for any of those... They aren't worth it. The first one is just a shape with some effects, the second is just a single brush, or possibly render, and the third is just a render with some effects. The second one isn't bad if it's not a brush or a render though. I recomend you add borders, and try to make them a little less simple. You really need to lower the price, since I've seen much better stuff sell for the same price. Actually, you should give them away for free. When I did art this simple, I did it for free. Nobody will pay for it, so give it away as practice. When you get better and have more experience, start charging for it. Oh, and don't ever use jpg. Use png.
Anyway, there's my input.