Collecting emails should be something you do on a regular basis. When you build a list, you can market to it over and over again. It's a bit different than paid traffic straight to a landing page or direct linking. In that scenario, you are hoping as many clicks as possible convert. When you are collecting emails, the same holds true, but you have a little easier margin to work with.
Think about these two scenarios
– You have a campaign sending traffic to a landing page promoting a dating offer. You pay for traffic and hope the visitors convert enough to cover your traffic costs, and leave you with a profit. Once someone converts, you're pretty much done with them.
– You have a campaign sending traffic to a landing page with an opt-in form. Just for example purposes say you get someone to opt-in for $1 (meaning you spend $1 on traffic for every opt-in). Now, you might have spent money without an immediate conversion…but once you have that email address, you can market to that person over and over. One email you spent $1 on collecting could earn you hundreds of dollars in commissions as they convert on the many offers you email out.
Most people start collecting a list, then stop because they don't see an immediate return. You aren't going to see steady conversions when you have collected 50, or 100 emails. You need to get to the thousands (this somewhat depends on the niche) before you will most likely see some sales come in. So, yes…in our scenario above, you might spend a few thousand dollars building a list before you see much revenue from it.
That doesn't sound real appealing I know. There are some ways you can break even, or even earn a positive ROI while you are building your email list. It's not a guarantee that these will always work, but it's worth trying for sure.
One strategy is to collect someones email, and immediately send them to an offer. Depending on how targeted your campaign is, and how creative you are with collecting opt-ins, this can work pretty well and it's very easy. You can also send them to a landing page with multiple offers, increasing the chance that they might convert for something.
Another strategy is to send your traffic to a landing page with an offer/offers that also has an opt-in form on it. You need to give them a good reason why they should convert and opt-in at the same time. You might explain how the visitor can get a great deal by signing up for one of your offers today, and get future offers sent to them by email.
You can, and should get really creative with this. There are a lot of cool possibilities, and if you get it right you can build a huge email list that pays for itself. It's not going to be overnight. I just did one campaign that took months to just start seeing some sales coming from my email blasts. You have to get out of the quick one hit mindset so many people have with affiliate offers, and start thinking how you can earn the most from each visitor.