_You have a few answers that tell you to back off immediately, that it is a joke or you are getting set up to be the "office mom". You have one answer that gives you a very concrete step by step guide on how to actually do it (only slightly tongue-in-cheek)._

_One caveat: if you simply do not want to do such a thing, are uncomfortable with the job itself, are afraid to talk with other people over the phone and such, then ignore this answer, go to your boss and just say no. If, on the other hand you have no problem with all of this, and are just unsure whether it will benefit or hurt your standing in the company, then read on._

Let me add a fully "pro party service" answer with zero tongue-in-cheek:

1. I have worked in 40-60 person companies, as well as in 10-15 person teams within much larger companies. I can very well see how such a set of persons could all simply be technical folks who have no pleasure and no interest in organizing parties or other social events. There was never a dedicated "party organizer". Sometimes there were folks who did big events, but they would not really bother about small things like a few people going to a bowling alley. So, there is, in my opinion, no immediate reason to suspect foul play.
2. I find it not very special that a new person is asked to do this. They are not asking you to do table-dancing on the evening of the party, but they are asking you to manage a small project. Period. It does not matter that it is about merry-making. It could as well be a customer event or whatever (be glad that it is not!). It still needs professional conduct on your side. Your benefit is that it needs no previous knowledge about anything whatsoever, so you are likely as well suited as everybody else. 
3. The actual "doing" should be quite "doable" for you. It is a simple process - find a location, check out all the details, organize payment and such. 
4. Be 100% sure about what you are *not* going to do. You are *not* going to hand-hold everybody to the alley. You are *not* going to serve drinks while there. You are *not* going to bring a cake that you baked at home. You are *not* going to do anything else than everybody else there. You can and should be upfront about this ("manage the expectations of your customer"). You organize the alley and maybe set up a Doodle to find out who is going to attend; you may help them distribute people into cars and such. But you are *not* going to be a handmaiden for anyone here. This is important.
5. Make it so there is a clear "handoff" where the bowling alley is now in charge. I.e., your organizational job ends at the point of time where everybody stands at the alley entrance, right before you grab your shoes. After that, you get the alley personell to do the rest (as usual - take orders, etc.). You can easily hand over the process of doing the bowling (making teams and such) to someone who has bowling experience. You are *not* responsible for whatever happens after this point. And then enjoy the evening!

While it may sound like a trivial setup to you, it may not be one. Being the guy (or girl) who can do such things in a company is not a sign that you are less worthy as a programmer. If you are afraid that you will always be the "girl" amongst the manly programmers and that they hence will think less of you, that may or may not be due to you organizing an event. But then you have a *much* different problem than a bowling evening anyways.

The benefits of being a person who can actually manage events on top of being a good programmer (or whatever job description you have) are plenty. 

* It might transfer into managing customer events or earnest internal events eventually. That is not an easy thing, it comes with standing, and everybody will be honestly glad to have you around. 
* It will let you grow as a person; you get to "boss people around", you get to do decisions without having to refer to some lead developer all the time, and so on. If you do it well, it will be huge for your self-esteem. If you do it bad, you will get very direct feedback, which is not the worst that can happen to a human. Responsibility.
* If you are slightly uncomfortable doing the actual deeds (calling the alley, trying to organize an event and such), that is a great opportunity to work on that. Communication skills and organizational skills are always useful.
* If you do it right, people will simply like you for it, which isn't the worst, in any company. 
* Your CV will contain "event coordinator", letting you expand on that in case you later find out that you like the job a lot. No matter that you are seeing yourself as a programmer now, there will be a time in 10, 20, 30 years when you are going to want to develop further. Starting out with relatively easy jobs like this is a *very* smooth path to more earnest endeavours.