Hi, first off, although it seems you're facing something new in business you really aren't.

I said so that hopefully you're stress level goes down if you realize this is common, and just as is common there are ways to overcome hurdles.
You seem to be doing the right things, your strategy of involving media and bloggers is one that many don't actually consider doing because the 'pressumed' labor it would entail.
Are you having our own articles written? If so make the copy targeting certain dilemmas... Not your product.
For example if your product solves many things (most do at various levels) only write an article per solution. This makes your ad articles more targeted, offer them to more targeted writers and bloggers. This should prolonge the life of the article because they keep what drives more ad views. Within the copy make sure to embed timeframes such as what's coming up. The ability to sign up for something later and that's the purpose of 'this' article...announcing something great coming...
If you have a blog, have those bloggers share one of their most popular entries to repost in your own article and then promote it. It should be something targeted as well.
FYI: social media seems to appear a no brainer process but in reality is a psychological game within each platform. Each requires its own penetration strategy- your efforts must be native ( non intrusive).

Another problem you might have is that your current website or landing pages aren't built to be viral. You see, you have a sales funnel right... You have to approach a market, find your audience, filter the best among the general, invite them over, get them to stay, get them to open with email, etc., then get them to share, then get them to return. Is usually on the return that they buy. This return could be same day or next year. But that's why the goal is to have them to share email, subscribe, etc. as your first goal. Not a sale. A lot of ecommerce stores deal with abandoned 'carts' that's because this is common online, but what's just as important is a way a to stay in touch.

I previously answered a similar issue question on my blog here:
http://unthinkeverything.blogspot.com/2015/04/your-continued-answer-to-clarityfm.html

Needless to say, if there are some products that are highly dependent on sales staff, so don't consider this a burden you might not need. Figure out the type of industry you're in and whether or not your consumers would benefit from engaged staff and Q&A to learn about the product, it's benefits, etc... Hire 1 person and try it out, or get a few under a commission structure.

Best of luck,
Humberto Valle
www.Unthink.Me