The best way to get leads for a B2B solution is to do prospecting research online.

What should you look for? Very depends on your type and stage of business.

Assuming you are completely new here are some questions that would get you started:
1) What problem are the business you are looking for having or what goal do they have?
2) Do they have a burning need to solve it?
3) How does what you offer help them solve their problem or their goal?
4) What stage of business are they in? What industry? What size?

And that is just for starters. Best approach for online research from there on out depends on your answers to the above. Once you have them, set up a call and I can help you further.