I know it may seem obvious but Photoshop. If you know someone with the program then use their computer and follow a guide. I am not the best with Photoshop but following guides it is usually pretty simple to accomplish what you want.
Most logo makers I have seen do not produce anything very interesting and the ones that do you suffer from seeing the same style of logo everywhere.
I hear the Gimp is nice as well, although I have not tried it much.