I am trying to set up an online business and would like to associate a toll free number. Does anyone recommend any vendor/s and/or share any experiences/horror stories?

Since you are a startup it is difficult to know the expected usage of your toll free number, but there are services like Grasshopper, specifically for companies like yours in order to get started. You get a set number of minutes a month with most of these types of services for a small monthly fee.

Sometimes it will be denied that their will be a time that their will be a problem regarding that thing. You can get toll free numbers in pbx101...Try to comfort your self.

My top 5 toll free vendors are:
FreedomVOICE, Halloo, LES.Net, RingCentral, Toll Free Forwarding. Check their website for more information on their toll free number services.