I recently ordered a pair of navy blue rubber boots from QC Supply, a catalogue offering products for those who work in agriculture and with livestock.
After many fruitless searches for a decent, plain, durable pair of waterproof rubber boots, I very fortunately came acoss QC Supply.
The pair I chose was the Women's 14 inch choreboot with a plain toe (a steel toe is also available) item number 71805 for $17.87, available in women's sized 6 - 11. They are blue and have a yellow cleated sole. So far I haven't experienced any instances where I was afraid of falling, they have such a good grip on the pavement/grassy/snowy areas. I was a little concerned that the footbed might not be that comfortable, but I was pleasantly surprised. Even if I am walking for several hours, doing errands and such, my feet do not tire in them. They are durable, but not overly heavy.
If you are looking for a good, serviceable pair of boots, they are well worth checking out. I know that I am very happy with mine and have already recommended them to several of my family and friends.