I have a wedding cake in a couple of weeks and they want the celtic pattern to go around each tier. I would rather use a impression/pattern than free handing it, does anyone have ideas for this? The pattern looks like captial a's and v's that don't overlap, if that makes sense

If you have access to some old ACD magazines, I believe they had the pattern in one of their issues a few months ago. I'm not at the shop or I'd flip thru my copies to find it for you.

Have you looked in Word under insert then symbol to see if they have those letters? Dafonts or fontsquirrel may have the font you need, too. Then just put those letters in the pattern you need, print it off, and pin prick it onto the cake.

I know this might sound a little weird, but bare with me.
Look up online tandy leather company.
They are a huge nationwide chain of leather supply stores.
They sell a awesome celtic impression mat that is usually used for tooling leather, but would be perfect for making impressions in fondant or maybe even crusting buttercream.

I looked them up for you, they have two of them
http://www.tandyleatherfactory.com/home/department/Books-Patterns/Craftaids-Individual/72035-00.aspx?feature=Product_8

http://www.tandyleatherfactory.com/home/department/Books-Patterns/Craftaids-Individual/72033-00.aspx?feature=Product_7

They are only $6 each and they are made of a nice sturdy plastic so definitely reusable.

hope that helps