Grabman,
Its better if the fridge is painted and is less glossy than the original surface. Must be clean and grease free.
Photocopy your image as big as you need. There are A1 size photocopiers available at shops like 'Kinkos' or 'Kwik Kopy'. That will cost a bit more than using the work photocopier.
If using the work photocopier then tape the A3/A4 pages together on the back side and cut off any overlapping (as this will transfer to fridge).
Tape this picture image side onto fridge. (You might need to reverse the image before photocopying to get it to read right (text especially).
Use a solvent that disolves the photocopy ink but does not disolve the paint you used on the fridge. This might be a bit tricky depending on the paint used and the type of photocopier (I haven't tried colour photocopiers).
Turps worked for me. Try metho, turps, acetone, thinners, kero. There are a heap of types that might work. Carefull on using gloves and ventilating room!!! Acetone kills.
Using a lightly soaked rag rub the back of the paper enough to wet but not to make the image run. You can re-wet as many times as you like.
Check the edges to see if the image has transfered, repeat if needed.
Use a marker pen and house paints to touch up image if you like. I used a perminant marker just to clarify a few lines didn't need much.
I wish I still had some photos of the final art....
I hope this helps.