In the season one finale "Kobol's Last Gleaming", Starbuck jumps to Caprica to retrieve the Arrow of Apollo. In season two episode "The Farm", Roslin's faction jumps to Kobol and (separately) Starbuck leaves Caprica. In the episode "Home", Starbuck somehow manages to rendez-vous with Roslin's faction in orbit of Kobol. Here Starbuck is piloting a Cylon Heavy Raider.
Now, how does a single Cylon ship manage to find its way back to Colonial ships? First of all, the Colonials were specifically trying not to be found by the Cylons, and were travelling around hiding, so it's unlikely Starbuck could just "find" the Fleet again unless they were at the exact location she left them at. However, even if Starbuck did know how to get back to the Fleet, how did she know how to jump to Kobol? The separation of Roslin's faction and their journey to Kobol happened after Starbuck had already left the fleet, so she had no way of knowing that this had happened. In the season one episode, Roslin clearly told Starbuck to "bring me" the arrow, not to bring it to Kobol.