Ad Networks - PPC - Landing Pages - Help

Hi there, new to the forum, have lurked for several years off and on though. I need a little help, and/or guidance.

I'm trying to figure out fully the art of PPC, but not only from the main 3 search engines, but also via native advertising and media buys. There's so many ways to drive traffic, the trick I guess is driving very targeted traffic, then getting that to convert.

My main focus is the financial industry and as far as I can tell you can hire and ad agency to set up display ads, text ads, etc. on the sites or portals you wish, OR, you can set up directly with these sites and set up a monthly spend. I've then been told that the higher you get up on the queue, the cheaper your clicks will become? This is where things get a little complicated for me....

For example, I have created a landing page and now I would like to beta test it and see if it a) converts to sign-ups; b) leads to any market activity for the featured company.

I would love it if anyone with some experience could help me out a little here with some opinions of the landing page, and where the best place to get started to get the most targeted clicks for the cheapest (haha, I know, everyone wants that)..

Thanks so much for reading.

All the best!