Just a quick tip, but any time you run an ad or post a link you MUST test it yourself. I wish I had a dollar for every time I clicked a link in an ad only to find a Page Not Found or similar error. I'm sure you have done it yourself, yet people fail to test their links.
Another good way to lose out on advertising efforts or dollars is by using shortened URL's with a service that can fail. Why take the risk?
It's not free, but you can buy a domain name from GoDaddy cheap and have 99 redirected subdomains from that. So if you paid $1.99 for a .info name, that's less than 2 cents each for a whole year and the odds of it not working are almost eliminated.
Just my opinion.