First off click on Images on the menu. You should see a list of different albums.
Fan Art is images drawn/submited by fans, Book and Game Images is images scanned or screenshot from games and books. Member Photos includes photos of the wonder Le members, this album is not viewable if you are not logged in! Submissions is the album in which to go to add photos to.
If you go to submissions to submit a photo, find the following.
Click on add photos, a box will come that will allow you to add a photo. Be sure to have your screenname in the file or caption name.
A mod will then create a folder for you in the correct album. After that you should be able to go to your folder and upload photos that way.
See a photo by or of someone else you'd like to comment on? Click on the photo and you should see a link that says add comment. Click on it, and add a comment and ta da!