I use 7Search from time to time and keyword targeting is paramount. Do not expect to "blow through" and make a good ROI. It's definitely long term. It takes time to test your keywords (usually in very small groups if you don't have tracking software to keep track). Delete the dead ones and add another group. Also run ads with variations on the wording. Same thing, delete the dead ones and keep the good. All this takes time so you want to keep the size of your campaigns small until you master your niche/offer.
In terms of not geotargeting efficiently, I also ran into this problem. 7Search and I identified that other countries were making it in by proxies and they have since filtered that out of my campaigns. But I think if you don't catch it, they won't stop it. You have to be very diligent on your referring IPs and countries that are hitting your landing pages.
On that note, you should be using landing pages that you control instead of sending direct unless, again, you have tracking software for that sort of stuff. Personally I use Prosper202 for tracking my PPC campaigns but that might prove daunting for a beginning marketer.
