any ideas for online stores?
i can spend only like $40 on her.
vintage stuff for her room?

it depends on what era she likes, what she needs, etc. you could try going to thrift stores. there are probably a million online sources of vintage "stuff" if you can think of a specific item , try ebay. in your price range, wall art might be a good start for your search. framed prints, or advertising art are fun and add to a room’s "look". good luck!
here’s a site, not for shopping, but for looking at all sorts of retro stuff…
http://www.bitlounge.net/retrolounge/fashion.htm