Where to Purchase a Pet Finch

1. Craigslist (free, adoption fees) - good to know the history of the bird
2. Pet shops (you may be able to save some poorly treated birds)
3. Private Breeders

There are many places you can go to purchase pet finches.
You can probably find them on Craigslist for free, or with adoption fees.
You can certainly find them for $10-20 (for society finches and zebra finches) at almost any pet store.
Or you can purchase them from a private breeder that will hopefully know more than anywhere else you would purchase a pet finch.
Guidelines for Basic Pet Finch Care

1. Proper Setup
2. Avian Veterinarian
3. Cleaning Upkeep

Get a wide cage made for finches, know a nearby avian veterinarian.
Like any pet you also have to keep up with maintenance.
You'll have lots and lots of splats to clean up, as well as cleaning the food and water trays often.
Pros of Having a Pet Finch

1. Unique Songs
2. Beautiful to Watch
3. Ease Your Boredom
4. Help You Wake Up

Pet finches can help you out more than you realize.
If you have problems staying on a normal sleep schedule.
Your pet finches will naturally calm down as the sun goes down, and they will start chirping away as soon as they see a glimpse of morning.
If they are near your bed at all, they will certainly help you improve your sleeping schedule.
Cons of Having a Pet Finch

1. Lots and Lots of Splats
2. Sometimes Loud
3. Difficult to Form Physical Bond

Finches must drop a number two every 10 minutes.
So there is plenty of clean up.
Fortunately they're small so you don't have to do any major cleaning until it starts adding up or the food and water trays are getting dirty.
They are also very difficult to handle, which makes it tough to trim nails or form a close physical bond.
Most finch owners say that you should purposely avoid physical contact as they don't like it.
I'm not sure that's true in every case though!