Spelljammer: Beyond the Moons
Of particular interest beyond all the great planets and sphere ideas are the 3.5/PF conversion rules, a unified cannon Spelljammer history, and a quick random crystal sphere generator. And more. A lot more
This is an active board discussing Spelljammer! Come see the forum where every week is Spelljammer week. Also, they are super nice, and if you're looking to track down an out of print book, or have a question answered, they are the people to help you!
Want more standup models for your Spelljammer game? Lose your old ones like I did? (I'm not bitter, I'm not bitter)
"If a player asks about oxygen and carbon dioxide, flip it back on them and ask how their character could know anything about that, and if they say they're asking out-of-character, ask them why it matters. If they ask in-character, explain it in terms of elemental forces (plants filter corruption out of the air or something). If they can't suspend their disbelief enough for in-game explanations to work, recommend they go play Traveller or something, since it would take too much time dealing with them whining about unicorns, dragons, elementals, planar travel and spelljammer being unscientific." - AuldDragon (Jeff) at the Piazza
Visit Melkot.com and print off some new ones!
Here's a link to the Google Plus Community Spelljammer
Finally, some really well thought out ideas can be located here about adjusting the Spelljammer rules in various ways
Last, but not least: