[Need] Help with promoting CPA Offers?

I am promoting CPA offers...should I have a landing page(before the offer page) that captures email of my visitor or should I not capture my visitor's emails?

I am using paid ads...I usually promote low payout($1-3 - email submit offers). So, is there any point in capturing email of my visitors?

I recommend going for organic traffic from search engines and social network. For that type of offers is hard to be on + $ if you don't convert almost all the traffic