It would be a good idea to stop buying her any more gifts, as she may see this as you trying to "buy her affection." As nice as it is to receive a gift, just one sweet one now and then is enough, while lots of expensive ones is suspect. Instead, take some time to talk to her about her interests and find out what she really cares about. Get to know each other first, before trying to ask her out. When both of you feel comfortable around each other and she is enjoying your company, then it's a good time to ask her out. And leave the next gift until you actually get a date with her, it'll be something for you to plan but keep it simple and sweet.