I'm in a similar boat to you - I've seen some contradicting advise, and it's not easy to figure out what to do.
I think there is multiple reasons for misinformation, and I don't think it just comes down to shops just wanting to make money (although I'm sure that's part of it).
I at least like to think that most people are genuine when they give you advise - the problem is that the knowledge that they have may have been from a bad source, so they believe what they say themselves, but they're passing on bad advice.
In saying that - agenda's of people with advise is a problem and needs to be considered.
There are people pushing their own agenda's out there.
Pet shops are one and has been mentioned.
Another example that's not pet shop related that I came across the other day is an online article from PETA saying that we shouldn't keep snakes because a survey in the UK showed that at least 75% of reptiles die from stress within one year!!!
Now is that an article that is about sharing the truth of the matter as it stands, or have they gone out of their way to find the worst statistic available to them possible to push a prejudice notion of what they want to believe because they were biased before they even started the investigation?
My thoughts are to ask as many people as practically possible - don't just get an answer, get the logic behind the answer and even if you think it sounds good and you agree with it - challenge it as best you can first.
As an example, you mentioned:
And another point of rigorous debate is the, and i quote, ''click clack'' my little boy is currently housed in. Numerous websites and python owners state that having him enclosed within a small plastic enclosure is better for him, with substrate, water bowl, hide and a heat mat is 100% sufficient until he reaches about 12 months old or so.
Yet there are many others who would argue until blue in the face, that doing so is wrong and that because a snake is a wild animal and would not be within such a tiny enclosure in the wild, that keeping a young snake within one will cause health problems.
The former advise sounds logical at first and when I first heard the same I thought - cool - that makes a lot of sense.
However I decided to play devils advocate to it and see if I could come up with a counter argument.... and I did. Snakes born in the wild are straight out of hatching and that's the only environment they know. All their movements are voluntary as well.
When you buy your first snake - it's been hatched for a while. What is it familiar with? Large open areas in the wild, or is a small click clack or small slide tub all it's ever known since it was borne?
I figure it's all well and good for people to argue the 'in the wild' point - but these snakes were bred in captivity so their previous experience is going to be different from day 1.
So now that argument (at least to me) has lost a lot of weight, and puts more weight on the breeders suggestions because they have more experience to back up what they say.
Then there are the people that have been in the game a long time but are running with old beliefs that have since been dis-proven as we have better understood snakes. For some older people - they may just go with what they've always known because it works for them and this is the information they will pass on. This isn't just a problem for herp's - it goes across almost everything. There is wisdom in age - but unfortunately a lot of old wives tails or incorrect notions can also be perpetuated.
Personally I think forums are great, provided you are aware that there is a high risk you will get some bad advice, but thankfully some people more knowledgeable will get on and correct others. Which one is right is the hard part.
In the end - I think you need to get as much information as possible from as many sources, weigh the credibility of the information and come to your own conclusions from that.