You have probably seen a lot of websites that simply seem to desperate trying to make you buy some "magic formula" from them, that will make you incredibly rich and you will not even have to work too much for it.
What could you possibly buy for 21-49 usd that can bring such great wealth so fast (according to them, you can start making this kind of money in 30 days)? Why do they go through all the trouble of creating a website, and in some cases, paying for hosting and domain name just to make you rich since they are already extremely wealthy due to their incredible programs?
Have you ever noticed how similar these kind of sites look? Take a look at some sites of this type and analyse them carefully.
They contain lots of huge fonts and bold text, highlighted titles with strong vivid colours and a lot of bad taste.
All of them contain "testimonials" from people who have used their system, and look how thankful they are! (lol). One other thing that will not be missing no matter what, is the statement where they can not stress enough to make you understand how crazy they are for giving you the opportunity to become rich for this small amount of money. You will feel like you are even crazier not to take advantage of this "unique" chance. Also they do not forget to let you know that they will raise the price pretty soon (lol). Just have patience and come back to that web page after a few weeks and see what happened; either the site will be gone, or the price will still be the same.
There is a lot more to say but I am going to add just one more thing: most of these sites have only one looooong page (hmmm... I wonder why).
I am sure you are wondering by now, how can this be possible. Basicly what most these sites are selling is the the actual template of that specific site, which by the way, they guarantee you that is so "proffessionaly designed" that it can sell anything from "successful systems" to ebooks and revolutionary drugs.

Don't be fooled by the fact that they will give you some marketing and maintenance tips and, in some cases, some software (like autoresponders for example)
that will help you organise your "business". These are just for distracting your attention from the real thing. You have just bought a site template for a price somewhere between 21-49 usd.
You may be telling yourself "ok, but 21 usd is not so much for a template that guarantees my sales". Totally wrong! It doesn't guarantee you anything! The quasi-success that they have is due to the fact that they are based on a lie and they speculate your desire of making more money with less effort! From a designer's point of view, those templates are obsolete. They look like the first websites that were ever published on the internet (and that is because most probably they are that old).
What I have written above was strictly related to a certain type of sites. However, there are some others on the internet that are more polished and they may even look proffesionally designed. No matter how tempting they may seem, keep in mind that they may be based on the same concept.

The main idea is that if someone is asking you to buy something like this, promising you that you will be rich shortly after that it is most probably pyramidal scheme and you will find yourself in a position where you will have to tell the same lie (that you are extremly wealthy due to this program) and hoping that some day you will make a decent profit. However, there are some guides out there that are also are for sale but their purpose is to give you practical indications on different aspects related to the "home based business" concept (how to develop an online store, choosing your isp and your hosting package according to your needs, explaining terms like "SEO", etc.) that may prove usefull, but you must know that none of them are guaranteing you great wealth. You should be able to find all this info for free though, if you search the internet for it. It is up to you if you have the patience to do a research on the subject, but before deciding to buy something like this you must first know what you are spending your money on.