hmm the inside of the letter A looks a little off seeing as its completely white when you compare it to the other letters, but overall this looks like something you could do in photoshop, though even then it would take some work and skill depending on what techniques are being put to use. Regardless if you were using photoshop then resizing is actually quite simple once you know how to do so, but I do have to agree with the question above:
what program did you use?
I might be able to help you out on how to resize images within the program your using without having to do so when you upload it to your image hosting site(Photobucket, ImageShack, etc.) Also for this site you don't want an image that you post to be any bigger then 600 pixels wide if you can help it just as a reference, but you won't have to worry about the height.
In Photoshop CS4 you can change the image size by going to the Image->Image Size and then change the pixel dimensions of the image. I am saying this by memory of course since I don't have direct access to that program right now though. This should be able to work in CS5 as well I would imagine so that shouldn't be an issue. This is of course once again just for future reference though. Also I've never heard of that other program so I might just check it out real quick. It would be nice to see some more of your work though.