Heh... Manaan and Tatooine swoop racing are both worth it... especially if you're a Light-side goodie-goodie who still wants the awesome toys you can buy towards the end of the game.
My strategy: Save after you beat each racing level/tier so as to avoid paying insane amounts of race fees.
I think I beat both Manaan and Tatooine with about 12-15 races each... Most of those being to get the 3rd tier. But 5000 credits/80 bonds is worth it.
Also: Sell all the crap you aren't gonna use. First time i played through, I hung on to just about *everything* which was really dumb.

On my second game (I'm about to beat it again), I've bought a lot of the cool goodies.
edit: The bonds are worth around 160 creds on yavin station, if you haven't heard.
