I agree that adwords are the best in driving traffic to your site. In contrast to this, adwords do cost a lot. but if you have the budget, why not. You can also optimize your site and do the basics, but this will not "quickly" give you "large" traffic right away. It actually depends in your needs. If you need a fast increase in traffic, I would advise to use adwords, otherwise, try to optimize your site organically. My two cents worth... ArdRigh
I will agree with the ways people have mentioned in this thread for generating traffic but personally the best way is going for Adwords campaign and taking part in social networking sites where you have a vast scope in getting a good amount of traffic.