3rd Party Services
I am not a big fan of 3rd party services. A lot of them take a lot of money away from you. TextLinkAds , for example, takes 50% of all sales.
And lets not forget you also have to first get into their publisher programs, which isn't an easy task if you run a new blog. A lot of the services tend to rely too much on worthless data like Alexa rankings and not enough on information like blog readership levels and where the links will be posted.
If you do not like doing stuff yourself, or if you have previously failed at selling your own links, then a service like TextLinkAds would work well for you.
Manual Labor
If you don't mind doing a little bit of work by creating a small "Advertise here" page, then perhaps you should sell your links manually.
The advantages to manually selling link space are pretty obvious. You get to keep all of the money from the sale and you have more price control. The downside to this is that you need to have fairly good proof that you get good traffic (or that you will soon get good traffic), and you need to experiment with link pricing.
Oh, and lets not forget that looking for advertisers is hard work.
About the Author
Jeremy Steele currently owns 3 blogs and a few niche affiliate sites. He has been studying SEO techniques for roughly 2 years and has recently started looking into new monetization techniques. His main blog is nusuni.com.