Becky,
You are amazing if you can have an amicable divorce. Unfortunately, that is almost never the case.
In California, you can do your own divorce papers. They are super easy when you aren't contesting anything. They do make you go to a Children of Divorce Workshop before your papers can be finalized, but it sounds like your kids won't have to be in the middle of a custody battle. The question I have and don't know the answer to is which state you should file in. You might want to research that as far as which one is simpler, etc.
I have helped people do their own divorces, where there were no children involved, and the only going to court that was necessary was for the actual filing of the papers and that was so the person that did the filing could get the filed copies to have the other person sign and the response was mailed in to the court. In that event, the only fees were for the actual filing with the court.
Since you have children involved, just make sure you know the laws of the states and have everything very carefully outlined. regarding custody, visitation, and financial responsibility, etc.
Best of luck to you and again, how refreshing to see adults acting like adults in a situation such as this.
Let us know how it goes.