yup..sounds pretty much obvious. happy tree friends. You even said it yourself to begin with. 2nd thing: you don't EVER ask a girl who she likes.. there's no good answer she will ever give you in that situation, unless you're Leonardo diCaprio and then you don't EVEN need to ask (:
That kind of question is what best friends ask, if you're into this girl ask her about what she likes in a guy (and read between the lines here - girls give a lot of bullshit), what makes her feel good, excited et cetera. If you know this girl for that much time you already have a ballpark image of this.. that and the fact that she's comfortable talking to you means you still got a chance. She even said she was into you so it's worth a shot.
What you gotta do is spend more time with her ( in person not on the telephone, that's gay ) make her have a good time, show her that you know her and understand her better than any other guy and then, out of the blue, hold her hand and tell her something like ¨you know, I've grown into liking you more and more these last few days, weeks, hours months (whatever!), I know we SEEM to be good friends, but we get along so well that I'm sure we can be more than that¨
Don't wait too long after asking this because it wasn't a question (: so she won't have a quick answer for it, but anything other than a slap or a straight out hysterical laugh and you kiss her.
Hope it works out for you, word of advice: next time don't wait to be thrown in the let's just be friends zone, act sooner (:
Oh and if she ever mentioned any other guy she likes or hates or whatever to you.. it's abort mission then. You're gay in her book. Or if you wanna be her shopping buddy be my guest (: