I've seen a lot of people around here interested in making remakes of campaign levels from Halo 2 (myself included), but it's not always an easy thing to accomplish. Unless you have two Xboxes (or a photographic memory), making an accurate reproduction of a campaign map involves constant switching between games. Well, no more! I've found a great tool that lets you explore the campaign maps of Halo 2 on your computer in 3D (haven't figured out how to make it work with multiplayer maps yet, though). If you're interested, here's my step-by-step guide to getting this great program up and running. [The following is cross-posted from HBO] So, with this program, you'll be able to have a model of a Halo 2 environment sitting on your computer while forging on your Xbox. Hopefully this will make the recreation of maps a much easier (and cooler) process.
Lol i use to have this when i used to mod halo 2 (original program where all modding tools were found was ump v5) but this looks great so now outskirts and cool forunner maps can be remade.
Or, if you're not-so economical and are willing to shell out a few bucks, the H2 strategy guide has the level layouts for all the maps, including multiplayer. It's helpful when you're trying to design a level.