Don't put it off until the season after next. There's *never* a good time to start racing, if you put it off now until 2014 there'll be a million even better reasons to put it off again in 2014. Also, people better experienced than me will be able to tell you when your ARDS test expires if you haven't taken out a licence, and all the expense of test, medical W.H.Y. will be totally wasted if you have to re-take it.
Strike while the iron is hot and you're still keen! Where do you live? There's some really good local series where you can get started for reasonable money - one in particular being the Welsh Saloon series at Pembrey which is offering stonking value at the moment. There are even some people doing arrive & drive at reasonable rates. PM me if interested.