New grad is new grad is new grad. I'm sorry to say it, because it seems to be a big surprise to many in this profession, but the more education the profession requires the more difficult it is to find that first job. Why? Well, because you have to be able to perform at a very high level and fairly autonomously. Who, without experience can be expected to do so?
Of course, that brings up the old catch 22, how do I get experience without getting the first job? Fortunately, nursing does seem to have some entry level positions, there are many professions, where it is much worse than nursing on getting a first job. Not that that helps you much.
I would suggest against sitting for the CEN, and suggest you look into volunteer work you can do, networking opportunities you can do, things like that. The more involved you can be with the organizations that might hire you, the more you can mingle with others who are in your profession, the better off you will be. Did you graduate with a BSN, or an ADN? If you have an ADN, then I would also suggest, starting school towards your BSN. It will defer any loan payments and help you stand out.
Another suggestion would be to widen your search area. Are you only looking in a certain geographical region (within x miles of your home) or for ER or certain types of jobs? You might have to settle for a med surg, or LTC or whatever job for your first experience and then migrate towards what you want. I have a co-worker who spent his first year at a LTC facility an hour from here, then got a part time job in our hospital, then got hired on full time, cross trained into the ER and is now finally coming to work in the ER full time. Not the fastest path, yes he has some classmates who got to the ER faster, but when all is said and done, he got where he wanted to get to. He also has a classmate that refused to take anything but the perfect job, she's still searching.....
Sorry if this isn't the panacea you wanted to hear. Real life often isn't. Sometimes the most direct way to get from point A to point B isn't the straight line you think it is!