What's the best way to look up phone numbers?

[Adam Adams]

Dear Wholesalers, Multi-Family Investors, Fix & Flippers, Real Estate Entrepreneurs, Tech Guys (and gals).

What is the very best way for me to get ahold of several phone numbers from a list I have pulled?

I am hoping to find something that will allow me to import an entire excel spreadsheet at once and for the computer/internet to reverse look up the number by using the name or address on the data file. 

My Acquisition team just heard about Mojo Sells through Joe McCall, which seems awesome, but it won't work if we don't have a bunch of numbers to call. I have a term in my head that I think I heard from Sean Terry a couple years ago called "skip trace" (I think) but I don't know what it is or how to use it...

Any help would be greatly appreciated!