Model species are well researched and many tools are available. For example, many methods can be used to get the promoter sequences from human being. What if from a non-model organism? This problem is becoming urgent since many new genomes are available.
ADDED: Maybe I should clarify the situation. The genome is newly sequenced by our group, so its sequences are available for us. But recently the sequences are not publicly available, so BioMart cannot help. We are annotating the genome. The CDS can be predicted. However, I have no idea about how to determine the promoter region for each gene.