What a great time to be in Delray Beach, Florida. Jan 2014-March 2014, as the locals call it, "season". Perfect weather, lots of action on Atlantic Avenue, and great beach days at the "Village by the Sea".
Looking early is certainly a good idea (and early you are).
My recomendation is for you to pick a building that you would like to live in (The Astor, Pineapple Grove, City Walk, Coda Townhomes, Atlantic Grove to name a few that I recommend), and get your paperwork in order. A small cottage, or duplex in the area is also a possibilty, but that is certainly up to you, and your price point (typically a nice turnkey rental for a three month term in season will rent for $4000 a month).
Once you have a good idea of where you want to be, and your paperwork in order, please feel free to call me, or any realtor of your choice, and we could start looking to secure you a residence.
Don't forget about the 11.5% Florida Bed Tax that you must pay the state of Florida for a short term rental (under 6 months and 1 day), and in order to secure a place, you will most likely have to pay for the rental in advance, and obtain association approval if you are renting a condominium..
Mizner Residential Realty LLC