You can find many websites for that on google. But apart from that let me talk about 2 important rules:

Rule 1. When you can get things done for money, don't offer equity. Equity is too big for you to let go, for something that can get-done by paying money (big or small). You don't know if the new person would gel well with your vision or thought process. You could get excellent people who can work for you as freelancers or consultants (it doesn't matter if they are expensive). If you need this person's services for all through the journey, then you can always look at a company to outsource the complete development and maintenance work.

Rule 2. If you still believe that the company needs a technical resource (more like a CIO or CTO), then go all out and find for the right guy, who buys your vision, idea, business model and willing to spend few years to travel the journey with you.

The equity percentage doesn't really matter because its more of a notional value and can be mutually beneficial.