Mcollier, I'm sorry you've had to wait so long for an answer.
Have you done a search on cathinfo, because there have been a number of homeschooling threads.
When we started homeschooling 30 years ago, there were few resources specilic to homeschoolers, and nothing specifically for Catholic homeschooling available to me at least. Nevertheless, they did very well and are all faithful Catholics, even though we used "protestant" resources, with the exception of history, which was offensive to little Catholic ears.
Of course we never used protestant for religion.
THe SSPX sisters (friends of my mother) sent me a big box of resources from their school. I also was lent reading books from some 7DAs and eventually found a secular HSing group a shared ideas.
At the age of your children thet should be concentrating on their letters and sounds and a good method is the so-called Spalding mthod. I am not up on what is available now. Ensure they develop a love of books. Most books we used were second hand, picking them up wherever we could, and steer away from modern which can be very ugly.
I developed my own curriculum, gathered from whatever i could find which was affordable.