I'm trying to observe the behavior of simple viruses in different environments. I'm just looking for simple viruses like the common cold and the flu virus nothing major. Is there a way to obtain them?
First of all, cold and flu viruses are not 'simple viruses', and they are not harmless. They kill tens to hundreds of thousands of people every year.
Secondly, this would depend highly on the risk group that the virus falls in. The NIH sets strict guidelines on who can handle infectious agents. Unfortunately, I can almost guarantee you that no one is going to give you even risk group 1 plant viruses, and they are certainly are not going to give you cold or flu viruses. Risk groups range from 1 to 4. To handle risk group 2 viruses, for example, you are expected to do so in a BSL-2 or higher laboratory, and anyone maintaining stocks of virus is going to do a hefty check of you and your 'facilities' before shipping you anything.
Furthermore, even if you did obtain the virus, you would need to store it or maintain stocks of the virus in tissue culture. Its not like you can just get an eppendorf tube of virus in saline and expect it to survive in your refrigerator at home, and its not like companies are shipping virus willy-nilly to anyone.
That being said, and at the expense of sounding self-righteous, there is really no reason for you to obtain virus particles. You should start by getting a book on virology and reading it. There is plenty of learning material both visual and written out there, and all I will say is if you don't already know how to culture virus or where to obtain it, you shouldnt be doing so, and no one is going to give it to you.
CDC Biosafety in Microbiological and Biomedical Laboratories: http://www.cdc.gov/biosafety/publications/bmbl5/BMBL.pdf
WHO Laboratory Biosafety Manual: http://www.who.int/csr/resources/publications/biosafety/en/Biosafety7.pdf
NIH guidelines recombinant nucleic acids: http://osp.od.nih.gov/sites/defaul/files/NIH_Guidelines.html
I think its great that you are interested, and it sounds like you are interested in histopathological changes caused by virus, so I have included some nice histo pictures below