Well, you're not alone, since probably 99.98% of undergrad women are single, and most of them want to be asked out on dates. So you can take comfort in that -- or be daunted by the amount of competition you have. Depends on where you fall on the whole "glass half full/half empty" debate.
Either way, my advice is this: live your life. Instead of waiting to be asked out, find out who you are and what you like, and I don't mean in a guy, I mean in life. That's what college is about -- getting to know yourself and figuring out what you want from life. The education you get there about yourself is every bit as valuable -- if not more so -- than anything you'll learn in a classroom.
Sure, dating is great, but it's just as important to work on growing as a (single) person. Try new things. Take chances. Value experiences of all kinds. Be bold. Make lots of friends. Learn as much as you can. Share yourself. Challenge yourself. Fail. Learn how to pick yourself back up after you fail. Have fun. Make memories. You will cherish them later, I promise you.
You've heard people say that we find love when we aren't looking for it. That's because when we aren't looking for it, we are living our lives to the full, and there are few things more attractive to a guy than a woman who's out there carpe diem-ing every single diem. We see a confident, outgoing gal who's having a great time with or without dates, and we want to come along for the ride because it -- and you -- look like a blast.
I'm not saying you have to BASE jump or wrestle crocodiles to get a guy's attention. I'm talking about living your life, whatever it may be, and not really caring if anyone notices or not. Trust me -- they will, and lots of dates will follow.