If you're self-employed, can't you mark out that time for antenatal like you would if you were PAYE?
I would investigate the hospital classes. Yes, it is all in books or online. But I did still find it quite useful to have someone to ask the really stupid questions that popped into my mind.
But the most important thing for me was meeting other parents. Don't be put off by your DH being away - I mainly made friends with the women at my NCT class, who I still see three years later. Your DH could join a later meet up of the group.
Great if you meet mothers at other classes too, but I found that doing NCT classes meant you met people at exactly the stage of pregnancy you are. When it is your first baby, a five week old is entirely different from a five month old and people you meet at other baby groups may not have babies exactly the same age. That to me was more useful than anything else as you could say things like:
"Is your baby pooing green?"
...and they were at the same place as me.
But don't worry, even without classes, there is always Mumsnet! 