What software do I need to separate colors of a Logo?

[Des]

I have two Company logos that I designed. Our Company wants to get them put on a Company t-shirt, an emblem on front and one on the back. The front logo has the colors black white red and yellow. The back logo has the colors black white, orange, and brown. The t-shirt company that we have to go through is a silk screening t-shirt company. They told us that we have to either draw 8 different drawings (one for each color of each logo) or they can do it on their "software" for $20/hour. They didn't tell us how many hours it would take and we can't afford to go up on our price per shirt. I was hoping maybe someone in our company has or has family that has, this software. My questions are what is this type of software called, what are some specific brands of this software, how much is it, where you can get it and how would I do what I need on this software? Thank you!