Hi,
You can always rely on social media to build a list, or at least gather people on your social media pages (fans, friends, followers, etc) This is the fastest /easiest way to start marketing.
But ultimately you want to have an auto responder list as your conversions will be much higher.
I am about to put together a small video for my JVs showing how they can promote my The Facebook ATM product without a list. If interested, I will be able to send you the link, or you can sign up as JV here and you will get notification right away.
http://www.thefacebookatm.com/jv/
If you need any help from me, just please let me know, I am always happy to help.
Warm Regards,
Georgina