I bought a solo ad from Holly Sutton for 200 clicks at $60 or $0.30 a click
Here’s my receipt:
Holly promoted my Top Plugins for WordPress site
Here are my results:
I received 390 clicks (190 extra) and got 140 subscribers for a 36% conversion rate and a cost per subscriber of $0.43
For the extra traffic and the low cost per subscriber I highly recommend buying a solo from Holly.