I've been looking everywhere and couldn't find one for free...I finally found This site (http://www.singermachines.co.uk/indstbooks.htm) which has a lot of manuals, but didn't find the one I was looking for.

Does anyone know where I can find a free manual for a Singer Merritt 8220C ?

My friend gave it to me with no book, and I have no idea how to work it :-/ I have the 10 piece assorted Kit of extra doodads too.

Go down to #59 for yours (nearly right down the bottom)
Singer Sewing Machine Manual Instruction and Repair Manuals (http://www.sewingmanuals.com/Sewing_Machine_Manuals/Singers.htm)

Scratch that, you have to pay, sorry!!

That's ok, that's totally what I've been dealing with since I got it >_>

They have a few videos on youtube,but not your model.