I've used adwords many times. I am currently buying traffic for a content website and I started yesterday. I checked the stats of the buy in analytics and it shows 0 visits for adwords campaigns...when obviously i havent bought plenty of clicks. What could cause analytics not to track the adwords campaign properly?
It does take some time for some cases, sometimes up to a few days. Make sure they are linked properly through Adwords and that the Analytics account you are linking with is its own account. You can not have different adwords accounts linked to multiple profiles within one GA account.