Although Craigslist has recently undergone some changes that I feel may make it less appealing to marketers, it is still a source of good traffic where people are in a buying mood.
I recommend using Craigslist only because it is free and you can spend 10 minutes a day putting ads up and you should see results.
The biggest problem is getting your ad to stick. If you blatantly advertise an affiliate product, your post will be flagged and removed quickly. The trick is to keep in mind what section you are posting in and how you are writing your ad.
For most products, there are a probably a couple of categories you could place your ad. I typically stay in the "for sale" and "services" section. Like I said, the real trick is getting your ad in front of the right people and in a manner that will not annoy people. Craigslist is known for finnicky users who spend hours scouring ads looking for people trying to promote products, even though it is not necessarily agains Craigslist TOS. Craigsllist does not allow you to link using an affiliate link, but you are more than welcome to link to your own website!
The other restriction is you want to keep your ads to a minimum. No more than 3-5 a day or CL will "ghost" your ads, meaning they do not show up in their results.
With all that said, I still think CL should be included, at least in the beginning as it will usually drive traffic in quickly. The downside is you have to keep posting and play the game of hoping your ads stay. It is frustrating to post ads and find out they were flagged and removed!
Example:
Let's say you are promoting a credit report offer that pays you when someone gets their free credit report. We don't want to come off as being a pushy salesman in the ad, so we have to think a little.
Maybe a good place to put the ad would be in the "services" section under "household services". Call the title of the ad "Protect Yourself from Identity Theft". The body of the ad would talk about how a great way to make sure you haven't been and do not become a victim of identity theft is to get a copy of your credit report from all three bureaus and possibly use some type of credit monitoring service which alerts you to new entries on your report. Link to your site at the end of the ad.
To insert a link to your site into the ad, use the following piece of code...
<a href="http://yoursitename.com">Click here</a> to view link
Just change the "yoursitename" to your domain. The words between the <a href="http://yoursitename.com"></> tags is what the viewer will see as a clickable link.
Again, while I would not rely heavily on Craigslist, I would use it to start generating immediate traffic. The real key is just testing and finding what ads convert well and stay posted on Craigslist without being flagged. Once I had enough traffic from other sources, I would probably devote much less time to Craigslist...unless you had developed a method that really brought in a lot of sales!