Good text/image editor where I can save as .png

[Mildredop]

A friend of mine has designed me a logo. I have it as a massive .png file. But I'd like to reformat it to use it on stickers and the like, as well as separate the logo from the text.

My friend did it all in Photoshop, but I don't want to keep bothering him with menial requests. What's the easiest way I can do this?

Thanks

 

[maflynn]

Pixelmator is a great app, I'd recommend that, if you don't want to go the Photoshop route.