Yes - you can get transparent sticky labels on a sheet (for PC use) or you could also use one of those "Dymo" tape label makers that you can get different coloured rolls of tape for - I know they do a white one (black print) and a mother-of-pearly stylee one (again, black print).
Or
You can get stencils if you dont trust your handwriting?
Or
Anyone else in the family who's artistic and could do for you?
Or
Some companies will do calligraphy for you for a price.
Or
Poleroid pics of your guest at thier setting???????....... (only good if you have someone on the day to take the pics for you - eg arriving at the church - or people could send you thier pics for you to put onto the cards!?)
Good Luck!!!!
