When I get whole chillies from the local BIR they are deseeded. I have a great method for doing this that I highly recommend. Just chop the stalk bits off the chillies, then put them in the sink. Run the cold water and between your thumb and forefingers roll and squeeze lightly from the thickest part at the top working down. All the seeds come out in around a seconds or two doing this. Without the seeds / placenta the chillies are less hot, so you can add more, getting even more chilli flavour. Try this method out. At first you might split the chilli a little near the stalk end but be more gentle and after a few it'll come naturally!