I'm always speaking to women at work. It's the best place to practice on them in a low risk environment. Hey, she knows you have a job!
Just go over and say hello and ask what she does and mention that you see her around. Say nothing about being attracted. This can get you in some trouble. If you can muster the strength, ask her out for a lunch and make it a business lunch.
Hell, I've got a real hottie from work coming over to my house Monday with some of my work friends. I'm going to convo her like crazy. It may come to nothing but it's a great way to practice some neutral stuff. I'm good at convo but I could always use the practice.