It shouldn't matter really. The fact that you care for her enough to want to buy her something is really sweet. But something shiny or you could take her to her favorite restaurant.
Something she likes, your girlfriend will love the gift if it has a lot of thought put into it. If it's something she likes she'll be happy that you paid attention to your wants. We don't know your girlfriend, so we can only tell you the basics like flowers and chocolates and teddy bears, but other gifts mean a lot more than that.
Dude you can't get a concrete answer form hear cause if I am getting this right you want some thing from the heart and some thing that means some thing to her. But that being said there is no problem getting ideas and running in a direction with it and making it yours.
if she collects things get some thing along thous lines "plush toy, porcelain figure" roses never hurt simple thing as a card that means some thing to you to. or if you can draw draw her some thing "favorite disney charter saying some thing nice to her"
Describe your ideal first date; Where do you go? What do you wear? How does the date end?
I would love anywhere. I would wear something sexy and revealing just for the guy. It always ends in his bed or somewhere dark. But, I like it other ways too.