Setting up a photoblog – help needed

I had earlier set up a photoblog in MT, and wish to convert to WP. I’ve already converted my weblog to WP (running on a test server).
I’m using the different entry fields to store the title, the url of the image, and a third box for information about the entry.
You can see it in action over here.
All the images are uploaded in a directory according to their category e.g url/cat1/some_pic.jpg. The url for the html files was: some_url/cat/ so both the html files and the pictures were in the same directory.
How would I go about making a similar photoblog in WP? Ideally I want to upload the file, have a thumbnail auto-generated according to a preset size, and a new entry filled in with the picture info (just like MT!) so I can then enter in the title and post it.
I’m using/testing WP 1.2, and still haven’t figured out how to do this. I don’t want to use systems like gallery etc, as this is more configurable and easier to use.