Using wedding stamps is a delightful way to personalize your wedding invitations and your thank-you notes. For the invitations, start with a nice photo of the bride and groom. It will be just over one inch squared, so you want to select a photo that will read well. Instead of a full-body picture of the couple, use their two faces. You could even use a photo-collage made with Photoshop Elements or a similar program if you wanted to.
You need to know roughly how many invitations you will be sending out. Then click on the image below to go to an excellent website for designing your wedding stamps. You can play with a zoom feature, and borders and colors, till you get it how you like it. Then order as many as you want, in whatever denomination you want. You typically pay with a credit card, and the stamps will soon arrive by mail. If you are in a rush, you can order faster delivery.
After your wedding, likely you will have some nice photos of the big day. You could easily create some elegant wedding stamps to use for thank you notes, featuring one of the wedding photos. I bet a lot of people would keep those as souvenirs!