I think there are two ways to do this:
1. You can check the ChIP-chip and ChIP-Seq data from GEO and ENCODE for your TF. This is the direct evidence that the TF binds to the targets. But the TF binding is a dynamic/tissue specific process, so make sure the ChIP-chip and ChIP-Seq experiment performed in the similar tissue/cell type you are interested in.
2. Or if you know the motif of that TF (check Transfac), you can use the motif to scan the gene promoters. If the promoter contain the motif (usually this region should also be conserves across multiple species), then the corresponding gene might be the target of that TF. This is just a computational prediction.