Upload, Resize, Into Custom Field?

I’m the editor of my school newspaper and we’re using WordPress to run our online edition. The layout is such that the most recent story will be displayed on the front page with an image to the left of it. There’s a bit of CSS involved, so I’m using a custom field to store the image URL.

When someone posts a story, they’ll need to upload an image (No FTP, preferably), resize it automatically to 400px by 350px, and then display the URL so they can copy-paste it into a custom field.

I doubt that there’s a plugin that will do all of those things, but what would make the process as simple as possible so that the other editors won’t get confused?

I don’t know too much PHP, but I’m not afraid to learn, if I need to use GD or something.