Is your house big enough to do it there?? Can you rent a little hall so that if it rains you are OK?? (I have had a rained out party before so am wary of outside!)
I have used websites to print out free invites for my kids, just google free printable invitations or similar its amazing what you can find.
Fruit kebabs are good, fairy bread (a must LOL) sausages/frankfurts are a winner.

I have a few kids party books that I can photocopy at work and post to you for ideas if you like??