Google must hate me because they've been giving me less money with AdSense and didn't send me any vouchers for AdWords - although I already started anyway.
Tips: RESEARCH everything to its minute details. And don't be afraid to spend money to earn money. That's what PPC is all about.
It's so easy with Adwords - change tiny details (like upper/lower case in your URL) and see what happens. One thing you might want to do is grab the Google Adwords Editor to change things in "Windows" (instead of online). Sometimes it's easier / faster than the web-based interface.