My family has just made the decision to homeschool our two children, 4 and 3. I am excited and a bit nervous as there is so much to learn. Does anyone have any suggestions on the best place to start?

IMO, reading, reading and more reading to them!  And lots of physical play!  You have time to read and learn yourself before they need any formal schooling, so you'll be fine!  Hope to see you at park day, where the kids will get plenty of play and you can learn from the parents. Good luck!

I agree.  I happen to be an Early Childhood Specialist, so I can tell you most experts agree, too!  The most developmentally appropriate education for a three and/or four year old is LOTS of exploration through play accompanied by meaningful conversations with you and the others in the family.  Read to them every day, let them engage in self-directed play, let them experience the town (construction sites, zoo, grocery store), give them chores (sorting the laundry, setting the table, etc.) and just go about the business of being a family.  They will have the rest of their lives to 'do school.'  
This will also give you a year or so to soak up all things homeschooling.  The public library has some great books, the internet is a huge resource, and of course, come to park day.  

So I basically just repeated everything 'yitlan' already said!

Enjoy this time with your kiddos,

I also have 2 little ones, 4 and 2, and i have been committed (in my heart) to home school them since they were born, but sometimes my mind has doubts.  I know this is the age to play and enjoy their free spirit, and watch them learn from every life experience.  However, as i watched every mother friend i have with children the same age placing their kids in preschool and sensing the mounting pressure from my extended family to do the same, i felt the need to reach out to a community of people with the same beliefs.  Besides joining the home school co-op i also checked out a book from the library called "The Art of Education" by Linda Dobson.  Her writing inspired me and quelled my doubts of my ability to give my kids, what she calls, 'family centered education.'  I'm sure there are many other books and periodicals by home school advocates, but for some reason this one helped me relax into the idea that we are doing just fine.
Welcome and i hope to meet you some day.
Deborahlise

There is a wonderful program that is held at the zoo and bio park for kids 6 and under called BioPark Beginnings.  I took my kids there when they were young and they absolutely loved it.  The link for this program is http://www.cabq.gov/biopark/common/feesupported.html
It's a great way to meet other moms and little kids and have fun while doing so.