What should i buy

that depends on your budget. if she loves to read, buy her a book written by her favorite author. is she into jewelries? get her a necklace with her nickname as pendant. but a trip for two to one of the islands in the carribean would be best.

A very pretty bracelet, a book on one of her interests?

How about a book if she like to read. Or a purse. Women love purses. Or you can just give her a gift voucher form a shopping mall. If she is very choosy then she can get something that she likes herself with the voucher and you can take the credit for it. I also love expresive greeting cards with gifts so try that too. Best of luck.

You'll never go wrong with flowers and chocolates but if want to be more personal you should ask her girl friends, that is if you haven't really a clue to her likings. You're the BF, think of something she's craving for.

If you can figure out something personal it will probably be a hit with her. What are her hobbies? Does she have a favorite restaurant or a favorite store? A gift certificate is often a good choice because she can get what she wants. An overnight trip to a bed and breakfast can be a fun romantic gift idea. :-)