Dear Steve, 

What I just wrote to 'Dazed' may help to you. It will also give you more light if you change the question. Instead of asking what you want, ask what God might want you to do. 

To find out what this might be take a look at all that he has done for you, take a look at the world around you and what it needs, take a look at your own possibilities (and don't forget to factor in the power of grace). And ask for help.  

My advice usually is: if there is no clear sign that there is not a vocation, if the thought has come into our head without us seeking it, and if our reasons for considering the priesthood are valid, then it is worthwhile to pursue it and find out more. Give God a chance to speak to you more clearly  

Happy hunting!