Welcome. And congrats on making your first post on martial talk!!! There are a few recent threads about this in the Muay Thai forums- you might want to have a read through the conversations there.
But basically- just get started. Find a good school near where you live, and get started. There's nothing that will get you conditioned for Muay Thai like Muay Thai!!!
However, if you feel like training in the meantime while you find a school, I will recommend a few things to help get you started. I should ask you however: are you totally unfit, or just new to the MA's? If you have never done any training in your life, and have no idea how to run or lift weights or stretch properly, then it might not be wise to do so without proper instruction. So the advice I will give presumes that you have some sort of fitness or familiarity with basic exercises like running, stretching etc. If not- then seek professional training advice before getting started- that's my disclaimer
First of all, start stretching once a day. This will begin to get you mobile and flexible- just make sure that you do a small warmup before you start stretching. I would also do some cardiovascular activity (i.e. running or skipping). That will help get your cardiovascular fitness up. If you know how to lift weights you can do a bit as well, or try doing pushup routines and lots of situps and crunches. You could try this 3 day training program for example: run on day one, then after you finish the run have a good stretching session. Then on day two you could skip for 10-15 mins, followed up with a stretching session and a pushups/situps routine. Then have day three off before starting this cycle again!!!
Hope this helps. I still recommend finding a school ASAP, get in there and train ur *** off!!!
Good luck
