Hi Christie,
I use my home phone line and my cell phone for business. I don't have a separate phone line. Mostly I list my cell phone as my business number. I did have Ring Central for awhile when I thought I needed/wanted an 800# but couldn't justify the expense. I know some people use services like Ring Central for forwarding, or for a specific ring from specific numbers if they are handling other people's calls, or for the voicemail. I know there are other options that people have discussed such as Grand Central, GotVmail, onebox and others. Just take a look at some of the specific discussions regarding phone services here and you'll get a better idea of what people are using according to their needs and costs. Try
Here and
Here and
Here.