Red, as you know, you are a dear friend on this board - just like a Bro to me. So let's analyze EVERY LAST AND SMALL DETAIL OF THIS, to really help you out.
You say that you were "sitting in my office this morning". Well, what kind of office is it? A corner office? Do you have lots of diplomas up and stuff? Women are usually attracted to power, so my hunch is that if you have a big Don Draper office then she was probably interested in you. Now... how long did this meaningless chit-chat last, and what - exactly was the subject? If the chit-chat was under 2 minutes, she's definitely interested - you make her uncomfortable with your manliness, and she wants to jump your bones, but doesn't have the courage to say so. Now anything between 3-8 minutes, that's the kiss of death to your romantic plans, because that's just meaningless chit-chat time. You clearly don't intimidate her, and you don't excite her enough to make her stay longer. My advice is that if you wanna be a playah, that you let her talk about herself - women like doing that. However, slip-in a few references to your yacht and the airline that you own in South America. Any conversation longer than 8 minutes and you're in golden - she clearly wants to spend time with you. Go for it and take a risk and ask her out on the spot.
Now, you say she was playing with her hair - what colour and EXACTLY how long is her hair? These make all the differences in the world. A short-haird woman is usually a lesbo anyhow, so don't even bother trying your moves on her. Chance are she just wants fashion advice from you anyhow. Give it to her, and get on with your work. However, if her hair is past her shoulders, you should always comment when women play with their hair like this. Psychologists believe that the act of wrapping hair around a finger is very symbolic of a phallic desire, like wrapping her tongue around your wang-doodle. Next time she plays with her hair, ask her if she'd like a pen or carrot to shove down her throat. This way you'd know for sure what the hair playing means.
This lunch thing sort of throws a wrinkle into my whole theory. See women usually want men to pay. Having her pay is a sign of her being an Ellen loving lesbo, as she's taking the power away from you. Next time tell her that you have an important conference call with the Tokyo office. Then give her your credit card and ask her to bring back sushi for two for both of you to share in your office. Then, ask her if she wants to shove the chopsticks down her mouth. If, however, she takes you up on your offer but wants Italian food, you know she definitely does not like you. No one finds Italian food romantic (an Italian bistro is romantic, but the food itself, with it's messy tomato sauce and garlic breath are not romantic).
As for this whole cock touching thing - I'm not so sure that's a strong sign. I had five different women touch my cock today while discussing file, riding the bus with me and working out with me at the gym. It generally means nothing. As per my previous suggestions, you may wish to ask if she wants to shove your cock her mouth (along with the pen and chopsticks). That may be a good indication of whether she likes you or not.
Good luck. I think if you follow my advice, you should have her in bed within about six months, or a sexual harassment lawsuit on your hands in two days
