Point taken Auk, but can us newbies get some points for enthusiasm.
Point being:
If you would be interested in Koi, you would not dig a hole in your garden, fill it with water, and dump a couple of young fish in there that you purchased at a garden center. You would start studying first. You would first study how to build the right environment. You would study how to grow them. You would talk with others that have real Koi, try and find a reputable seller, and maybe join a club. You would not start buying a price winning, expensive fish, as you know you're inexperienced and it might die, and you need to learn and gain experience first.
I'm not trying to discourage you, but the fact is that on this forum, most post from newbies are people that have the wrong idea about bonsai, that have not studied the subject, that do not realize how much time, patience and knowledge it takes, and that often never come back as their plant could not be saved and they gave up.
That people do not return to the forum is NOT caused by the reactions on the forum. People that really want to do bonsai, do return, and do show the progression of their trees. That makes me enthusiastic.
I regularly look at 'Marktplaats' - the dutch E-bay. Most trees offered are mediocre, at best. However, I think there are more used pots offered than actual trees.
Sometimes it concerns huge collections of pots = without any tree in 'm. Reaosn? Many people do the exactd same thing. They 'were always interested in bonsai' and suddenly picked up the idea to start growing them. They get into a collector's frenzy, buy loads of plants, don't know what to do with them, kill most of them, and end up with a collection of useless sticks in pots. Then they give up and sell their now useless pots.
I'm not trying to discourage ayone. I'm just trying to be realistic and make people uderstand that if you start bonsai, know what you are starting with, and that it takes lots of time, patience and study.