I'll just add to this thread by reiterating what some women have mentioned. take her shopping!!
My boyfriend's birthday is coming up, and he loves to fish. I was never really into it, because i don't like to do something I'm not good at. But once i got to browsing around fishing supply stores, and doing hours of research (because I only wanted to get him the absolute best baits and stuff) I began thinking that I could really get into this. There are so many options!! I was used to the good ole fashion worm and paperclip routine that I had no idea what the world of fishing was all about!!
Shopping! take her to a basspro store and she will drool.. well.. i did..