With my 2 yr old, I started at just under 5 mos. My doctor had given me the go-ahead and some information on feeding at our 4 mo checkup. I decided to just wait and see and start him when I saw all the signs and thought he was ready. For mine, he was starving one day, and nursing didn't cut it anymore. I tried for a couple days, but even though he was getting his fill, he wanted more. I could just tell. He had been watching us eat and reaching for it, and could sit up, etc. I started with cereal (I can't remember what the reason my doc recommended starting with cereal, but she said it was best, so that is what I did.) I did cereal from a spoon mixed with breastmilk for about a month. Just a little bit after nursing. Always do solids after nursing, about 20-30 mins afterwards, so that you don't decrease your milk supply. Don't do cereal in a bottle, that is usually only recommended for babies with reflux to help keep the food down. You want baby to learn to eat properly.
I used the Super Baby Food book also, along with some websites. The book was very helpful. I always had a couple of jars of stuff in case we went out, but at home we did all homemade from the beginning. I chose go about it very casually and not make my own yogurt and stuff. You really can be as involved or laid back about it as you want to be. I used a Magic Bullet to blend in and loved it. I also had a tiny Cuisinart food processor (the smallest one) and I used it as well. Some things blended better in one or the other. I did a lot of baking, because you could do bigger batches for the same amount of work. I would bake a few things at once, like sweet potatoes, squash and regular potatoes, and then blend them all. You are going to be able to find lots of good produce soon to choose from to make your own. Summers are much easier to find good stuff than winter.
I definitely recommend getting the book if you can, and here are the three websites I liked best:
http://www.homemade-baby-food-recipes.com/index.html
http://www.wholesomebabyfood.com/
http://weelicious.com/