Yeah, freelance homeworking jobs are big scams.
That's not to say that you can't work from home, because you can. But getting random jobs from the internet will be a recipe for disaster. They will be low-paying, if you ever get paid at all, and you'll have to dodge various scams.
Instead, make a list of what you did before DS, and then approach companies offering to do those things for them. That way, you'll get to work directly with reputable companies, you know you'll get paid a decent rate, and there will be plenty of work around. It's just being confident and determined enough to get started - which you'd need to do anyway, because internet jobs have high applicant and rejection levels too.
Also remember to declare any money you make, and to consider paying your own NI incase you need it in the future.
Oh, last points - What Wilson says is correct. You'll need to find time to communicate with people during the day, and sound focused and professional. So you will need either a good routine (I know some people who work very part time during their childrens' 2 hour nap) or some help with your son.