Almost every state you need to be a broker to own a property management company, however there are other ways you can do this:
#1 You can hire a broker to be broker of record but you will probably need to be licensed as an agent if you are doing any of the management side of the business.
#2 You can get your license as an agent and simply do property management with the blessing of your broker, I know Keller Williams & RE/MAX in my area will allow you to do such things and they will let you keep the majority of the profit.
In my state you would only need to be a property manager for about 3 years before you could be a broker (you would have to provide proof that you assisted in management and did leasing), so if you are motivated and take your brokers classes right after getting your licenses you could be a property manager in a few years depending on your state and in the mean time you could build up a book of business to take with you.
When it comes to answering the actual questions you asked here are a few tips for building the business:
You can pay for leads, company's like all property management will give you leads for a price.. Typically it ends up being $25-50 for good quality leads that will make you that money back in the first month.
You can call expired listings and listings that have been on the market for a while
You can market to agents (most agents want nothing to do with the business of property management)
You can be a vendor at local real estate clubs like REIA or ACRE
If you join a large company you can ask your broker for 5 minutes in your meetings to talk about property management to the other agents in the brokerage.
As for the other question I have never used that software, I have heard good things.. The only software I have used is propertyware but that is for larger businesses.
Good luck!