Lots of couples are making their own invitations, rather then getting them printed by a specialist wedding shop. There are all sorts of ways you can make your own.
You can design your own invitation (templates online can help with ideas), buy good-quality paper and print them out yourself at home.
You can go to a specialist stationery shop (like Daintree in Dublin) where you can choose your paper, then use the printing templates on the Daintree website and print out the invites yourself.
You can design your invitation yourself, then take it to a local print shop to be printed.