!rant

I started a company with a few other guys 2 years ago and we're finally about to have the money to hire more people. However, I'm the only software engineer and I have no idea how to find the right candidates or how to give interviews. Has anyone here hired before, where do I start?

Could you tell us your website uri?
I think it's hard for potential candidates to figure out whether your company is interesting, if they don't know about the products, coming from it ;)

Think really hard about what skills the new hire should have. Don't ask random questions. You want someone that fits in the team and that brings a new set of skills. The best test is real work. Give candidates a real task and pay them for it!

Don't just look at their skills and degrees. It's way more important that the person fits in your team. You will have to work together everyday and you want it to last. With motivation everything can be learned.
Maybe start with a intern? Also to train your hiring skills and to know how it feels to have an other person with you.
Place offers on your website or maybe some at the university.