Seattle Red of TheMiniaturesPage.com has put together two very handy references for 15mm figures. These are profusely illustrated with detailed lists and comparisons. A great tool for the 15mm gamer!
The first is a list of manufacturers of 15mm landing craft. This includes extensive illustrations, and you can download it here
The second is a list of manufacturers of 15mm LVT and Amphibious vehicles. You can download this document here..