There are LOTS of recipe sites out there --- but the one I use most often is
AllRecipes. There's a
huge database of recipes that are actually submitted by real people rather than professional chefs and cooking magazines, and the recipes are all rated by members (membership is free) so you have an idea of what you're getting into.
If you're looking for something a little more exotic, try
RecipeSource --- they have a great selection of international/ethnic recipes, which you can explore either by geographical origin or by type of dish. You could cook her a theme dinner from Hawaii or Thailand or wherever embodies romance for you, and even set the scene with music and decorations to match...
And last but not least, if you're willing to try something more ambitious, the reigning monarch of recipe sites has to be
Epicurious. Their database is made up mainly from recipes originally printed in Gourmet and other cooking magazines. I've had some great successes with recipes from here --- Kahlua Espresso Brownies are always a huge hit, and the Lemon Currant Almond Pilaf is excellent too. (I make the latter with cranberries instead of currants, and the red berries and white rice make a great contrast... Good for Valentines' Day!)
Hope that helps! I've got lots more suggestions, but I think this ought to get you moving in the right direction!
--- sweetstuff
(... who, when not making love, is a compulsive cook ...)