The best way Ive found to mark plants is to use plastic knives. On the side I write(with a sharpie) the name of the plant then stick it into the ground. Works great. I saw this in a magazine once. Every now and then I have to go buy a bag of plastic knives, around $.99, when I cant get enough...
I went to Barnes & Noble one day and started pulling out all their gardening books and flipping through them. This is the one I decided to get. I LOVE this book. Its great for beginners and shows you how to do so much stuff. I give it two thumbs up.