You'll be able to race swoop bikes on Taris, Tatooine, and Manaan. The Taris race is deliberately easy, and quite difficult to lose, especially since you have multiple heats to attempt to get the best score. Unfortunately, the swoop races on Tatooine and Manaan are much more difficult. These are twitch games, no doubt about it, so casual RPG players may find these challenges a bit out of their league.
If you intend to fulfill the ancient prophecy and bring balance to the swoop tracks, you'll need to master a few basics of the game, namely:
The first tenet is obvious: if you hit an obstacle, you will never be able to get the time required to win, at least at the highest level of competition, since they will usually knock at least a second off of your time, and your margin of error is going to usually be down to the tenths of a second. Obstacles are bad; avoid them.
This leads into the second rule. As random as the placement of the booster pads may seem, there are definitely lines that need to be followed and planned out for each race track; this is as true for swoop racing as it is for any track in Gran Turismo. Occasionally you may swerve to hit a booster pad, only to find that obstacles are in your way, and that you're out of position for a pair of booster pads on the opposite side of the track. This isn't something you can magically know ahead of time, however, so you'll need to take advantage of the practice runs that are available on each track. It can help to actually go as slow as possible for a couple of the runs, to see how the booster pads are laid out and where the obstacles are placed. The tracks look a lot different at high speed, though, so run them as fast as you can for a dozen repetitions or so, and you'll be well on your way to mastering the course.
Last, but not least, you should develop an instinct for when to shift gears. You can madly tap away at the A button if you want, but every time you try to shift when your bike isn't ready, you'll take a small speed hit. If you wait too long to shift, however, you'll essentially be giving away speed to your competitors. You won't be able to take your eyes off the track while you're racing, so you should develop a habit of keeping the acceleration meter in the lower part of your field of vision, and hitting the shifter right when it first becomes available.