It's up to you to decide whether and how much you want to pay. As a web site designer I have often seen people who believe that their business will boom once they get a web page. Unless you promote your site, you will be very disappointed. It's kind of like having 1000 fancy business cards printed up and then locking them in your desk drawer. You have to get out there and pass them around for them to have any effect.
Search engines are a small part of getting noticed on the internet.
Besides explaining how to get listed on the search engines the articles here will discuss some of the other ways that you can promote your site. I will be adding to these articles as time permits so keep checking back for more ideas.