Lookin to expand from FB.
Just a few general Q's:
1. Initial investment needed?
2. Difficulty in optimizing to at least get -20% ROI or better?
3. How essential is having WRW in all of this?
There are a few recorded webinars. Plus there is a webinar coming on in two weeks, where you can get all your questions answered (in the announcements section).
1. Intial investment needed? $500 is just fine.
2. If you read the case studys we have here and the info about media buying on the forums -20% ROI or better is highly achievable.
3. WRW is nice, but not essential.
best words of advice I can give you is lean how to make creatives.....creatives that get CTR/CVR.....get fast an good at it.....it just makes doing buys of any kind much easier.....
You should do one more of those magic dust videos showing how you created 10 banners in 2 minutes that achieve whopping CTRS 
i can only make creatives in 110x80 
posted one at bluehatseo.com, read it....
I was watching the Offervault's webinar on Media Buying and it covers all the things present in Mr.Green's link 
here you go, mate:
http://stmforum.com/forum/showthread...3038#post23038
Thank you!
check out the sitescout webinars on here (use search function) and i def. agree about the creatives, they are your lifeline on media buys, you need to get really good at pounding them out fast. I recommend you use bannersnack.com its very easy to create banners. Of course photoshop is good and fireworks but my go to banner creator is bannersnack hands down.