If you want to try It out, simply sign up for a Bing Ads account, then sign up for their Bing Webmaster tools. After validating that the site Is yours, you will have a free $50.00 code to use on Bing Ads!
I didn't even know this until like 5 minutes ago lol.
I already had $25.00 In my account, so I just did It to have $75.00 :p
Sadly this Is only for US Accounts. Not sure If It can only be used on new accounts, but for a free $50.00 of advertising It's worth trying :p
Just thought I would share for anyone looking for free PPC advertising, or wanting to try out Bing!