...how do the people from igem and other things make DNA or read DNA and I do not mean RNA.
It depends on how you want to make it, there's actually couple of different ways.
You can for example make DNA by chemical synthesis. In this way different nucleotides are joined together in sequences. By chemical synthesis it is possible to create any sequence wanted, but the limiting factor is the lenght of the synthetised sequence due to the relatively frequent errors.
more of this here: http://en.wikipedia.org/wiki/Oligonucleotide_synthesis
Second way would be to use PCR, but for this approach you need a template sequence that is then copied. For a template sequence you can use basically any other DNA sequence even ones synthesized chemically. This way it is actually possible to synthesize also longer DNA sequences by combining chemically synthesized oligonucleotide primers and templates and PCR or ligating enzymes.
More here: http://en.wikipedia.org/wiki/PCR
and here: http://en.wikipedia.org/wiki/Gene_synthesis
The easiest and most reliable way to multiply DNA, if you just want to multiply it not edit it anyhow, is to just grow it in suitable bacteria (E.coli) as a plasmid. This is basically the routine way of cloning DNA and if you do DNA work you always end up in cloning the wanted product into a plasmid that you can then maintain in bacteria. And if you have suitable restriction sites in your plasmid the easiest way of editing DNA is to use restriction enzymes and just cutting and pasting pieces of DNA together.
Some more in here: http://en.wikipedia.org/wiki/Recombinant_DNA
In iGems constructs
I'd say that they have cloned the different parts with PCR and added restriction sites around the genetic elements (genes, promoters, etc.) and then just cloned the parts into suitable plasmids. The plasmids are then just grown in E.coli and purified.
Dr. Wikipedia answers
Also where do I order synthetic DNA
I needed to edit this answer because I stumbled upon these links to different firms that sell synthetic DNA and basically anyone can order it (I suppose).DNA2.0GeneScriptEurofins MWG OperonGeneart