Breaking into the college level

[JJ]

Contact a couple of schools close to you and offer to work Fall scrimmages for free. They appreciate having umpires, especially ones they don't have to pay for, and you'll get a feel for what ball is like at that level.
Do the camp/clinic thing, and rub elbows with as many assignors as possible. Let them know you're new, but want to work.
Find several veteran umpires and let them mentor you - they'll give you insight to the higher levels of the game that you'll appreciate having.
If you have the time and resources, go to a pro school. They'll give you the tools and the confidence to move up.
Have fun, work hard, and good luck!

JJ