Hello and welcome!
I am getting married in Manuel Antonio in Jan 2010, and decided to rent a big house for the wedding/reception and place to stay.
As far as luxury accommodations, you will not find super nice mega resorts in Costa Rica. It isn't anything like Cabo or the Mayan Riviera. Almost all the all the hotels are boutique hotels, and will be small, family run operations. Not that that's bad, it's just harder to know what you're getting.
Personally I am so glad we decided o Costa Rica! Most all our friends and family have never been, and the price is turning out to be cheaper than anywhere else! Also, it such a beautiful,amazing country that I am so glad to visit again!
You may want to look in to renting a house, there are so many in Costa Rica for half the price of a Cabo/Pedregal mansion. The houses seem nicer than the best hotels! Here's the site I rented my house from :
Manuel Antonio Costa Rica Vacation Rentals, Villas & Houses, Luxury Beach View Rental Homes & Lodging Accommodations - Rent a Holiday House, Villa, Home
Well good luck and happy planning! There aren't many of us Costa Rica brides!
Eliza