Go call around to your friends, and find yourself a good divorce attorney.
Find copies of all retirement funds, stocks, bonds, tax returns, deeds, any documentation of anything he has of value, and make copies.
Open a credit card in your own name, with only you on it- make sure they don't make him an automatically authorized signer. Open up a bank account in your own name, too, in a different bank than you've been using.
Find cash. You're going to need it. make sure you grab enough to pay your lawyer a retainer fee- they can take other payments out of a settlement, but you'll need a retainer. Unless he owned property before you married, pretty much everything should be 50% yours. It's against the law to hide marital funds,so look around for any accounts you may not know about, before you declare divorce war, or it will evaporate.
Don't get mad, just get to work to secure your future. He walked out of yoru marriage, so now it's a business deal. Make sure you get everything you are due, and make sure you get the best help in getting it. Your friends will tell you who that would be in your county. Don't waste any time getting an appointment,and a legal separation. Take your marriage certificate when you go.