Hey choosing gift for your wife is most difficult and time consuming exercise but at the same time its fun also. you know you got to be creative and intelligent enough to do that. the method which I adopt is to keep listening to her likes and dislikes, her interests and the things she want. then whenever I want to but a gift for her I buy the thing which she mentioned most.
I mean there are always instances in your life when she mentions that she needs this or that or a friend of hers just want that very good dress keep getting the clues and you will eventually make her happy by getting the things she actually wanted. last valentines what I did I managed her to go to a gift shop with me and asked her to buy a soft toy as big and cute as she can(she is very fond of soft toys) and I said I m buying it for a mutual friend. after she selected I bought the toy and when we reached home I gifted it to her. she was so happy I cant tell you. So that can be another way to buy a gift for your beloved.