do you have a preferance for revolvers, or autos?
and if revolvers, single action or double action?
do you reload?
i would say for hogs, nothing less than a 10mm (properly loaded), but more realistically you are looking at 41 magnum, 44 mag, or 45 colt. take a look at smith and wesson, ruger (i cant believe i just said that!!!) and freedom arms (a serious inverstment).
answer the above questions and you will get answers that are more specific.