8bitartwork only supplies artwork.
To get your design printed onto all kinds of different goodies, check out the reputable suppliers below and follow the on-screen instructions.
When you get there, just pick the "upload your own photo/artwork" option.
UK
Cafe Press UK
Spreadshirt UK
T-Shirt and Sons
VistaPrint UK
USA
Cafe Press USA
Spreadshirt USA
VistaPrint USA
NB: 8bitartwork.com does not endorse any of the above companies or services.