Traffic is the biggest roadblock to the growth of any Internet business. I have purchased, signed up for and researched a huge number of traffic growth programs out there and almost all are not as fast at growing your list as they promise, and quite a few are great at wasting your time.
After my experience with purchasing ads on Google, Pinterest and Facebook for promotion of my online business I found that the only realistic and quick way to grow my list is to purchase solo ads.
I use Udimi because I like the way the vendors are set up and I have great signs ups and a few sales with them.
The vendors offer a transparent view of their past performances and what they offer. You can narrow your niche criteria also. I have my favorite vendor and he is responsive to questions (even a newbie like me). Here is a link to Udimi and be sure to check out my favorite vendor, Indulis Staskiewicz. Udimi Solo Ads
P.S. You will need to sign up to check them out!