J.C.
Hi, I am a cytogenetics technologist and since you are of Ashkenazi Jewish descent, I understand your concern since this group can be carriers of genetic disorders. I am not sure if genetic testing is covered by insurance before you conceive...usually it is covered afterwards if there is reason to believe something is wrong with the baby. And it depends on your insurance policy as well, I'd give your carrier a call. However, there are groups that offer subsidized testing, I did a quick internet search and found one in Chicago (I see you are in Oak Park) and by pure chance (aren't you lucky!) they are having an educational session and screening testing for exactly this reason on Tuesday and I guess its $90 a person or $36 for students. Sounds like they will have people there to answer your questions as well, I'd check it out.
Here's the link:
http://www.jewishgenetics.org/?q=content/march-genetic-ed...
Good luck, and try not to stress about it. Since you are a mixed faith couple your risk is less...even if both parents are Ashkenazi Jews and both carriers, the risk is 25% for the baby...which in the genetic world is pretty significant, but that is worst case scenario so I think you will probably be pleased with what they have to tell you.