If you are coming from abroad, we generally recommend that you print your invitations locally since it is too complicated, costly, and time comsuming to ship them back and forth if there are printing problems. However, if you are looking for unique, illustrated invitations with matching thank you cards, take a look on www.celebrateisrael.com for some lovely ideas.
Birkonim come in all shapes and sizes. You can order small Birkat HaMazon cards, Birkat HaMazon pens, leather bound Birkonim, or a beautifully illustrated Sefer HaKiddush that includes Birkat HaMazon. You can also order siddurim and chumashim to be used by your guests at the event and kept for many years afterwards as a souvenir of your special celebration.
You may also want to consider magnet invitations and party favors—people put them right on the refrigerator so they don't get lost, and they continue to be useful long after the party's over.