We did ours with cardsandpockets.com. Was all pre-cut and we just designed the invites as we liked. We also added some heat embossing, which made them look professional and added a personal touch to the design. Here is a good tutorial: http://www.weddingbee.com/2009/01/14/heat-embossing/
You can get embossing supplies at any craft/scrapbook shop. I would recommend Bonnidée in Point Claire (http://www.bonnidee.com/en/). They were very helpful and gave me a on the spot demo when I stopped in on how to emboss. They also have some good samples and ideas for wedding invites and am sure they do workshops.