Ribbon snakes eat insects, but they also need to eat fish. They're often nippy, are fairly specific about heat and humidity, and hide ALL the time. They are NOT a beginner snake at all.
If you want a snake, your best bet is to either get over being squeamish, or not get one at all. I personally have 7 pet rats. But I also have a snake. He's a Pueblan milk snake. He won't get big enough to eat rats. He eats pre-killed frozen mice.
Feeding live food is not only cruel to the prey animal, it's also very dangerous to the snake. I've seen a 10 foot burmese python killed by a single rat bite. Because rodent bites are puncture wounds, the wound couldn't be found and it go severely infected under the scales. By the time the vet could find the wound, the snake died. All in the same day.
If you don't want to feed rats, stay away from the pythons and boas. Some of these get big enough that they need to eat rabbits. I recommend anyone save experts stay away from the larger pythons, anacondas, beauty snakes, and other varieties that get larger than 4-6 feet. Especially if you don't live with someone else who's also familiar with snakes. NO snake over 6 feet should be handled alone, no matter how much experience you have. And DEFINATELY stay away from hots (venomous) varieties. Even the rear-fanged varieties, who arn't generally lethal.
Colubrids stay small enough to only eat mice. Great beginner snakes are Corn Snakes, who get a large variety of beautiful colors, California King snakes, and Milk snakes.
Kingsnake.com is a great place to get in touch with breeders, and also see what's available in your area. There's also a Canadian and UK forums that have classified areas and breeder postings. THere are also a LOT of helpful links to very informative sites.