Google the keywords related to your website that you are looking for and then check out the websites in the result and email the webmasters and ask them if they want to be partner up and exchange links. Try to give a service or product for free, in the return ask for a link to your web site.
Google doesnot like paid links and the website that are selling links will be droped out of google, anyway i think link exchange will help a lot and no one needs to buy a link.
