There are many services out this for a simple data play (FullContact, PIPL, Inflection, etc). Our group has a similar service, but we don't simply supply the data we match it with your desired business outcome and build propensity models.
All the above groups (including us) don't cover the entire market, so for that reason, you really need to do a test set with each group and see where holes are. Many of our clients create a sequence of runs with the services hoping to get to 100%.
*The sequence above will be dependent on your use-case. The above is for illustrative purposes only.
No matter which group you decide on using, you will most certainly benefit by blending the results you get from your data providers.