What is the advantage of one way links? What should I look for when paying for them? What's the benefit of 2 way links compared to one way? What should I watch for when buying 1 & 2 way links so I have no issues with google?
One way links are favoured much more than two way (or reciprocal) links by most of the search engines, because two links are easier to get by swapping links and has nothing do with the quality of your site but you can get one way high quality links only if your site is a quality resource to your visitors. One more thing, don't buy any links because Google also penalizes the sites who buy the links and in this update Google has done that. But if you are really interested in getting some links then you can higher a company which can build one-way links for you without buying any links. You can PM me if you require any Link Building Service you can also visit our SEO Company.
One way linking will be good if the link topic is related otherwise I do not see any advantage. Paying for one way linking will be good if you can draw additional traffic with it. I do have people paying for one way linking.
If you're looking to collect link-juice and relevancy, I'd avoid reciprocal link building. Google has massively devalued the reciprocal links, plus there's many better ways to spend your time link building! If you're looking for a good overview of the principles of link building and the best (white hat) methods to use, check out the Link Building Guide at SEOmoz.com. You get the article free as a registered Premium user, or you can buy the article separately for $30. Either way, it's a good read and very valuable for a newbie SEO.