Have you put a profolio together and given it to your previous employer?

It would be good to follow up your discussion in writing. why not send or take over a letter setting out your skills and abilities along with samples of your work?

I agree that giving people the option of contacting you by email is the best way to go. And yes, if they already know you then you should remind them of how much cheaper it is to hire a freelancer, especially one that they already know.

Let us know what happens.