Well, Alan, looking at your current situation, I think you'll be way better of if you start with reselling - it does not require you to spend lots of money to buy all the hardware, software, products, have staff to manage it all.
Just find a decent reseller package and simply start with this. Then, if you think the business goes well and you understand how hosting business works, maybe it'll be better heavily invest in it then.
However, if you have a cable modem, you can host yourself if you follow this step by step guide:
http://www.dslwebserver.com/
Best,