I do not run a vps provider neither host related, but have used google adwords/admob before.
Google adwords is like gambling. If you know what you are doing it may work, if you don't know then good luck.
That said you have to do a lot of research before spending any $. Google has a lot of tools that can help you a lot and you really should master those ad planing tools before running any ads. Google (the search tool) is really helpful as you can find a lot of good resources on how to best spend your ads money.
I will emphasize this, it is a gamble, know your odds and how to bet and it may work.
edit: be prepared to lose a few bucks, your first ads campaign will barely work .