Stationary:
For your invitations, response cards, thank-you notes, and programs, consider making them yourself. You could print them on parchment in elegant Olde English and Gothic fonts (widely available for free download). For an extra special touch, seal the inner envelopes of the invitations with wax seals.

Guest Book:
Use any bound, blank book that appeals to you. You could use it as-is or cover a plain it with dark velvet or brocade. Use a fancy ostrich feather topped pen in black or another dark color. Or use a calligraphy felt-tip pen in dark color or silver or gold.

Getaway Vehicle:
The most gothic wedding getaway vehicle would be a hearse. However, this could really freak out conservative family members. But even more important, there are no seats in a hearse (except for the driver), which makes getting in and out difficult for any passengers.

A terribly romantic option is a horse-drawn carriage. Check your local phone book for companies that provide this service. Some may let you decorate the carriage with ribbons and flowers in your wedding colors.

A very elegant option is renting a vintage car, with or without a chauffer. Cars from the 1920s and 1930s are incredibly opulent, but even cars of more recent makes can be quite stylish. Of for a more irreverent getaway, look for a classic 1950s roadster with tail-fins.