Sports Direct. Loads of different trackie bottoms.
Depends what impression and look your wanting to portray.
Personnally, I went to a local ish company and explained what I wanted. They gave me a draft, I approved and went from there. I purchased my tops, jumpers and fleece seperately from another supplier and sent them in to be embroidered.
It costs a little more for embroidery compared to prints etc but Personnally I think it looks more professional