Lead Lists

I have spent a couple of hours looking over lead lists on the Internet. I have talked to a few people who have tried to purchase a lead list for their response. Generally, I have not heard anyone say it helped their business grow. I have heard that is brought in one or two leads but that is all. I am sceptical about any lead generation system. Where do they get the names? How often do they verify the information? They give answers, but I am not sure the quality of the responses. No matter what there has to be a strong sales lead list in any business. Creating new contacts and finding new prospects is what makes a business grow. If anyone has found a strong sales lead generator or method let me know, but it looks like it is just hard work.