The premise of your question, that methods that have worked in the past suddenly and magically no longer work, is not correct.

No lead generation method should be used in isolation. But phone prospecting and direct mail still work...especially when combined with other methods.

Really look into things...and test. Don't just blindly believe what the marketing department of a marketing company tells you about the effectiveness of their service. Many "white papers" are actually sales documents in disguise, directed to devaluing one marketing method in favor of the one the seller is offering.

No magic bullet exists. I recommend picking two or three methods, committing to them, and working on integrating their activities.

For instance, you'll probably need one method to pull traffic out of a platform. Facebook ads is an example of this. But does the marketing funnel end there? If you're a newbie I suppose it does. But experienced marketers know you can't just throw an offer in front of someone who clicked on a FB ad: it almost never works.

The funnel has to have a next step, a next method, for the prospect to move to. So they are directed to sign up to the autoresponder series (email marketing). Or a trial of a site membership. Or to complete a quiz. Or fill out a request for a mailed CD.

Emails in the series may direct the prospect to a video sales letter (VSL). That's hosted on a web page and a third component of the funnel. We're at the conversion tool now.

Lead attraction >> Warm-up funnel >> Conversion tool.

Each component can require its own method and they all need to work together. You could try to run everything in an email series, I suppose--use an email in the series as the sales letter--but the traffic has to come from somewhere. And that will require an additional marketing method.

A factor that stands out to experienced marketers as a "newbie alarm" is someone trying to combine traffic generation and conversion into a single step. You have to get good at drawing the right traffic (pre-qualified leads) first...before you start trying to nail down conversion. Otherwise you can't test and you can't understand your effectiveness. Newbies want to make traffic and conversion one step, and that's a mistake.

So your lead generation strategy should be:

1 > Identify your customer avatar

2 > Traffic generation from a platform (FB, Google, Bing, direct mail, inbound phone leads from a postcard, getting the idea?)

3 > Lead capture into a remarketing funnel (FB pixel, autoresponder series, CRM with follow up calls scheduled in a sequence)

4 > Conversion via tested method to understand which is most effective and cost-effective (high ticket closing call, VSL, print sales letter by direct mail, webinar to application to closing call, etc.)

I hope I have opened your mind about the process and possibilities. There's no magic bullet. It's a system and you have to test it...develop it in consecutive steps, making sure one step functions correctly before moving onto the next. Otherwise you muddy the waters and can't tell what you're doing--even if you're "successful" you won't know why and won't be able to duplicate the results.