Registry info in invites is a huge no-no. I know there are people who aren't offended receiving gift info in an invitation, but others truly are. I'm one of the later who sees it basically saying, "Please come to our wedding! Be sure to bring a gift, and by the way, THIS is the gift I want." You invite
people to weddings, not
presents... Sorry, I didn't mean to get carried away... It's a pet peeve...
Anyway, other posters are correct. You can include registry info in a shower invite (though, showers are really only for family and friends, not necessarily every female on your guest list), on your wedding website though a link that must be clicked on to be accessed (so not the first thing people see after your names), and through word of mouth. When people ask what you would like you might say something like, "We don't expect anything at all, but we are registered at _____." (Or, "we are saving up for _____," if you would prefer money in which case you also wouldn't register which is a big hint you'd rather have cash without rudely demanding it of your guests.)
You also never mention gifts unless asked. I know brides who didn't include gift information but then talked loudly to anyone who would listen about where they were registered and what they expected to "make" off their weddings. TACKY! A gift is optional and is at the discretion of the giver. The receiver has no part in the whole process but to graciously say thank you.
Good on you for trying to be a delightful and polite bride!