Grandma publisher

All right, I’ll admit it, I’m really a grandmother who is trying to publish some books for my son.  Long story short, he’s in prison for a crime he did not commit (really long story about a vindictive ex-wife who made false accusations in order to gain custody of their children).  In order to keep his sanity while going through the extremely long process of appeals, he has turned to writing, and along the way has discovered he has some talent and enjoys what he’s doing.  He’s written several books, but I’ve only gotten one ready for publication (check out the website at jcallenbooks.weebly.com).  I have to confess that I’m really out of my element when it comes to web design and promotion.  So far I’ve used my social network to get the word out, but that doesn’t seem to be working very well.  And with a grand total of nine books sold so far, there’s not really any money to spend for professional help.  Any practical suggestions?