1) add three image blocks each with an image one third the width and float left.
2) group images together in photoshop and place the one resulting image in the block.
3) write a new php block that will take three images and do the work automatically.
I think an easier way to do this is to add a "Layout" to your page. Click "Add to Main" and choose "Add Layout" from the popup menu. Enter 3 columns and 1 row. Now you have 3 slots in your page, add 1 image block to each of those slots and they will line up horizontally.
Welll, it may not actually be called "Add To Main". What I mean is, when you are logged in to your site, and you go to the page you want to put these images on, and you click the "Edit Page" button at the top-left of the toolbar, then you get a bunch of editable areas on the page which have red outlines around them. At the bottom of each of these red outlined areas are little grey areas with names like "Add To Main", "Add To Sidebar" -- but they may be called something else depending on your site's theme ("Add to Footer", "Add to Container", "Add to Main Content", etc.) -- it's always in the form of "Add to _____" though.
2) group images together in photoshop and place the one resulting image in the block.
3) write a new php block that will take three images and do the work automatically.
Hope this helps.
Steve