Just thought I’d give an update on this thread, especially to the ones that asked to let them know how I got on. Well after a week or so of phone calls with a few companies and agencies I have had 3 offers this week for weekend shifts.
I am working tomorrow with a company that subbies to a large parcel firm, doing trunking work. The owner says that I can do as much weekend work as I want, but I am only going to do Saturdays as another firm wants me to do every Sunday as they have contracts with a couple of supermarkets. That is also trunking from depot to depot with maybe the odd supermarket delivery. Both of these firms have said that I can work Saturday and Sunday if I want, but for now I am doing a day with each and see if I prefer one over the other
The third offer is from an agency but is further away from where I live than the other two so the other 2 are my preferences
All in all, I am more than happy with how things have turned out.
I just want to say thanks to those that offered some good advice and not so much to the merchants of doom that said stuff like there is no work for weekends only and I was out of touch for even considering it 
Turns out there’s plenty out there if you are proactive!!