Keep in mind that you can probably pick up a very nice, healthy, normal male ball python(if you go for a ball python) from reputable breeders for as much or less than it will cost you from a local pet store.

SOME local pet stores are perfectly fine, some are amazing, some are downright horrible. I'm lucky that there is a fantastic place that specializes in reptiles, with some amphibs and fish and exotic mammals, near where I live. However it seems that most of the country lacks a place like that, and most people looking for pet snakes just check out petco/petsmart.. They are known for not keeping great care of the snakes. Many people have purchased snakes from big box pet stores to find out the snake is sick, won't eat, or has other problems.

Another great option you should look into is local reptile or pet shows/expos. These are great for having a large variety of options to choose from when looking at snakes. You can probably pick up feeders and supplies there as well(though it is highly recommended to have housing setup well before you purchase a snake).

As for snakes that are good for beginners/first time reptile or snake owners? You'll get a ton of different answers. Most people almost always mention ball pythons and corn snakes as some of the best beginner snakes, and I'd have to agree, I've had experience with both and any 8 year old with a brain and the willingness to read a few care sheets can provide good care for either.

Other species to look at:
Western Hognose Snakes(top of my list for what I want to get later this year)
Carpet Pythons
Boa Constrictors("BCI" boas specifically)
Kingsnakes
Milksnakes

One thing to note: After deciding on a particular species, be sure to do plenty of research about husbandry requirements. Each species has its own particular needs, and the ones I listed above, although all are fairly easy to take care of, have specific needs.