I don't think that anyone is ever "ready" to have children...but you have to take the leap and do it! I have two children and I can't imagine my life without them! There will always be bills, there will always be something that comes up that wasn't in the "budget" or planned. If you keep waiting until you think you're financially ready you'll never get there. Honestly, I think that children just make everthing better!
The other problem is the longer you wait the slimmer the chances get for woman to get pregnant. I was always worried about getting pregnant before I was ready and when I wanted to start having children it was harder than expected. It took 18 months to have my daughter, and I'm glad that I hadn't waited longer because who knows what could have happened to my body while I pushed of having children.
There are some things that you just have to hold your breath and jump, and having kids is one of those things! They change your life! There's no better gift than the gift of being a parent!