An excellent resource for moms introducing their infants to solid food is the book Super Baby Food by Ruth Yaron.
I used it with all three of my girls, and we never had any issues with colic, rashes, or allergies. Our kids have always been healthy and strong, and love their veggies!
This book was a recommendation of a friend of mine. I have since found out that many of my husband’s friends — like him, very health conscious — have successfully followed the recipes and suggestions of this book. They have some of the healthiest children I’ve seen.