How original do articles need to be???

Hi

I'm fairly new to IM compared to a lot of the people on these forums.

I'm trying to follow a process step by step and see it through to the end without distraction by other methods.

I have built my website, primarily for adsense at the moment. 50% of the articles on the site are original written by myself and 50% outsourced to articlez.com

the article quality there overall is very good but seems to not be of a consistent quality.

I am now starting to promote my website. it will have quite an in depth network of articles to a wide variety of sites. I'm starting with ezinearticles at the moment and goarticles. later i will venture out further. I'm following the method outlined in 'the profit loophole' to link build and promote my site.

I have outsourced a few articles for ezinearticles as i know they are quite strict and articles have to be very original and of high quality there.

My question is.... how unique do you have to make your articles? For example in places like squidoo, propellor, livejournal etc.

i don't know how well i can afford to outsource for all this on a consistant basis. I'm quite happy to take my already good quality articles and change them around a bit. But to make every article completely original sounds quite a hassle and quite time consuming.

What would actually happen if i was to re-submit an article i've already written to another website? would google spank me or something?

Also what if I was to change the wording around, but base it roughly around an article I've already written? Would they be able to tell?

How do you guys go about promoting your sites with articles? What have you found from your personal experience? What would you recommend?