My advice would be:
-Start with a blizzard sorc for mf
-Get to A5 nightmare baal and do baal runs until you're level 75. You can get through normal and nm just by playing public games
-Find a 40s armor and 30s helm, and put flawless topaz in them
-Farm the act bosses and superuniques in nightmare (Andy / Countess / Meph / Eldritch / Shenk / Pindle) . You will be able to find all the low level stuff you need (peasant crown, viper, mosers, magefist/frostie, waterwalk, spirit, insight, etc)
-Once you're decently equipped you can move on to hell with your sorc, or make whatever other new character you want