Search engines like Google frown upon link buying. What about bartering? For example, I offer to exchange products or services in return for links to my site.
i think exchanging products and services in return to backlinks to your website is much better that buying or direct exchanging links. This method is widley used on blogs, where at the end of the page usually is a backlink to the theme creator ant to the hosting company.
I agree with this, but also offering a service may be a little better as well. I think you are fine though.
Offering free tools and services in return for free one way links has been practiced and exercised with success by webmasters online and is a great way of link building over the net but the tools need to be of high quality to work actually.
There's nothing wrong with exchanging goods or services for a link to your site. If the other party agrees to it then why not? In fact IMO it's perfectly normal and have done it myself. I think a lot of people have. Just good quid pro quo and link buying can often be dicely and uncertain as you don't always know what the quality of the links will be. Hope that makes sense.
Offering to exchange products or services in return for links is a good idea. Its also a good idea to start a backend blog for your product website, and post so very good content blog posts, then syndicate the posts via twitter and digg. You will get people linking to if your blog posts are good, and these are the best kind of links.
I have bartered for links with great success before. Just approach Webmasters who could benefit from something you offer, and whose traffic is related to your Website. It is usually very easy to gather several incoming links this way.
This is both detected algorithmically and reported, to be subsequently checked manually. As to the question by OP: I can't see why bartering is better than selling - both ways you are manipulating search results.
Indeed, it is yet another form of manipulation. I wonder how G would react to reporting "link bartering"? That would be an interesting test. As one poster pointed out, it occurs all the time when sigs are included at the bottom of open-source software like forums and blogs.
Buying links won't affect your website ranking in the SERP's in a bad way However, still one way links are the best.