Virtual Sales/Marketing/PA required

I am running a training business alongside a full time job which i hope to give up as my business grows. I am looking for an assistant to work from home and assist me initially one day a week with the following tasks as i just dont have time.

Take incoming calls via skype (at the moment no more than 5 a day)
Deal with queries
Take bookings
Contact potential customers and try and sell them training courses (commission will be paid on top of basic for every course you bring in)
updating websites
Registering courses online
processing certificates
sending mailshots and emails
everything else !!