@KitKat's mom I'm a newbie here myself, having joined just a few weeks ago. But I have read a lot of information that has posted here and the folks here are awesome in trying to help each other with our diabetic cats. I'm sure you are reading through a lot here.
Definitely take up
@Kris & Teasel 's suggestion about sharing the information. People respond fairly quickly. You can start getting advice from these folks while you still look for a vet.
As for food, this is a site you will want to bookmark:
http://catinfo.org/chart/index.php Dr. Lisa Pierson, DVM has done an analysis of cat food and you can use this as a guide to select food from. You'll see a lot of posts here about food.
When you get a chance, get your signature set up so people can automatically see some information about your cat such as the insulin, if you are home testing for glucose levels and what meter you are using if you do that. Information on how to set up the signature is
here and for setting up your profile
here.
If you aren't home testing but want to try that, there is lots of advice here about how to do that and there are videos--I'm sure someone will post those. There is also picture of where best to poke for the tests on here--search for the phrase: Sweet spot It may sound scary at first to home test but you will get it down quickly and most of the cats get used to it. I only started a few weeks ago and I'm only using a lancet now and my cat knows this needs to be done before he eats. He's not resistant at all.
If you decide to do home testing, there is a great template for a spreadsheet here that you can set up. Then people can look at your test results as they give you advice. Information about that spreadsheet template is
here and once you get it setup,
here is information on understanding it.
These folks are great here so I'm glad you found this community.