The scenario: In the not too distant future, someone ran just the right genetic algorithm and figured out how to make a warp drive. It can travel to distant stars! The only problem is that optical technology hasn't really caught up, and the sky is big, so really the crew is only vaguely aware of the position of the largest planets in the system they are warping into.
They are on a mission of exploration, dammit, and explore they will. Presume that they show up somewhere about Earth distance away from the approximately sunlike star. Presume that there are planets similar to those in our solar system floating around (so sure, there can be a rocky planet around where Mars is, and why not a large gas giant or two out in the outer reaches, but not much further than Saturn and not much larger than Jupiter). Presume that the warp drive makes it possible to reach all of those worlds. Finally, presume that they don't have access to "planet scanners". They've got what we have - optical and radio telescopes. How do they know where the worlds are, and how do they localize themselves with enough precision to navigate?