I also use psyllium, but I really like using tea that helps me go. Traditional Medicinals, which you can buy at your local natural food store, has a Smooth Move tea that is pretty gentle and works well. The main herb that makes is work is senna, but I am not sure how to take that separately from the tea. I am sure you can find it online somewhere if the the tea is too pricey.
If you live near an Asian supermarket, they sell Dieters Tea. I have used that too. There is extra strength and regular strength. The extra strength made me feel like I was going to die. I was in a pain for about 24 hours, so try something gentle. The regular strength was ok on my tummy.