Oh, and for those of you who enjoy guns, especially those who like custom-made weapons, the "Big Game Hunters" sourcebook will be for you. Although it has Cretasus-oriented stuff, most of it can be used in any d20 campaign setting. You'll LOVE the equipment chapter! Aside a long list of mostly hunting-related real firearms, like the Winchester 45/70, Sharps "Big Fifty", .505 Gibbs, and Holland & Holland .375, I've got a section dedicated for the machinists and those PCs who are wealthy enough to have customized firearms built. Note that this is even partly historical, as many of the great British rifle companies produced custom-made weapons for their own wealthy customers.
The customization section starts out with a listing of guns of various historical tech levels. According to Joseph's listing of tech levels, the lowest one with guns at all covers firearms from matchlock arquebuses to Kentucky rifles and Brown Bess muskets. Next comes "break-open" single-shot and double-barrelled rifles, plus revolvers (the only repeating firearms in this section are rifles with revolver chambers, which exist both in the game system and in real life). Finally, we have everything else, from bolt-, lever-, and pump-action repeating firearms to semiautomatic and automatic weapons. The listing of regular guns will have a wide variety of pistols, muskets/rifles, and shotguns, with a glossary of gun terms to explain everything to those non-NRA members out there.
Now for the good part. Machinists in various colonies, "lost" or otherwise, will be making firearms for their neighbors to make up for a lack of traders coming in, and some may be restricted to various tech levels. Every historical rifle or shotgun type---12 gauge, .22 Magnum, etc.---will be put on a basic table covering stats and prices for a single-shot, break-open weapon. This is followed by a listing of options, each with its own price, which you can use when figuring out the price of your custom-made firearm. Want a magazine weapon? Fine, just pay for it, the amount of money you shell out determining the capacity of the magazine. Want a repeater? Then pay for that as well. For those of you interested in initiative issues, pump-action guns work slightly faster than bolt- or lever-action ones, but are less accurate and reliable. By contrast, bolt-action rifles are the most accurate and reliable, but the slowest-working, while lever-action guns are in the middle in all categories. Of course, in our gaming universe, we've included a stabilizer that will make pump-action guns just as accurate as any other---IF you're willing to pay the price.
There are plenty of accessories you can buy, such as telescopic, laser, and sonic gunsights, muzzle brakes (for increased power and accuracy), silencers, flash suppressors, etc. The stock magazine will be a big hit, I think. Imagine a strip of cloth or leather the length of a shotgun or rifle stock, covered on one side with Velcro and on the other with loops for 6-8 (or more) shotgun slugs or rifle cartridges. Load the thing up, slap it on the stock, and you have an emergency supply of ammo with you at all times. And yes, you can put one of these things on each side of the stock at the same time. And if you have a clip-fed firearm, we have the Redi-Mag, which fastens itself to the clip-feed section of your gun. This thing holds TWO magazines at once, and when the first is empty, just drop it and slide the other one in place, saving reloading time early in a firefight. You could even use a variant with batteries instead of clips for energy weapons.
If you want to pay the money for it, you can even have literally "tailor-made" rifles made. In this historical case, you either send your measurements and stats to the gunmaker or go yourself to be thoroughly measured and weighed, and he crafts a firearm designed to be handled by a person of your exact height, weight, arm length, etc. Depending on which method you use, this can give a +1 or +2 increase in accuracy, but only if the gun is being handled by you or an identical twin. It's like having a magical weapon that only grants bonuses in combat for one wielder.
Lower tech firearms can be modified as well, but be careful. A revolver variant in the musket age means having multiple BARRELS on the gun, each of which must be rotated in place. There are also historical breechloaders, but the metallurgy of those times was so primitive that a lot of the propulsive gases leaked out the breech, so you increase rate of fire this way only at the cost of range and hitting power.
The treasure section details costs of sample Earth animal trophies---lion heads, bearskin rugs, etc.---as well as items such as rings and items useful on safari, such as collapsible bathtubs. Finally, there's a section on the duties and problems associated with the job of great white hunter, as well as a list of scenarios. The book will come out next year, and remember that you can use the bulk of the stuff in it on any world or planet. There are plenty of mundane animals in the D&D rules already, and the less-fancy monsters will make good faunas for other planets. Imagine a world where the vertebrates have six limbs, for instance. This could give you wildlife such as dragons, harpies, gargoyles, griffins, hippogriffs, pegasi, etc. Look for it when it comes out!