it seemed as if they were planning a second season from how it ended. but one was never made, so the ending is just simply disappointing. ugh... ):

There's a spinoff to Outlaw Star called Angel Links. If you remember that episode where the Outlaw Star gets detained by this security force led by a guy that looked like a dinosaur, yeah, it's those guys. Characters from Outlaw Star also occasionally make cameo appearances in Angel Links.

I tried rly rly hard to like Angel Links, but it kinda sucks. It has a few kickass moments, but overall I think it's mostly crap. :(

I thought the ending to Outlaw Star was pretty good, but I also agree that it seems like there should've been more. There's a manga that I believe is still ongoing, so you should maybe check that out. Mangas usually offer quite a bit more story than the series.