Setting up to design a proxy server

[George Levy <glevy@xxxxxxxxxxxx>]

I am a beginner in this field. I intend to get Linux and Squid, to 
design a proxy server but I am at a loss to pick the right version. For 
example Linux can be obtained free on the web, or a CD for $32.75. On 
the other hand the Red Hat Enterprise Linux AS 
<https://www.redhat.com/apps/commerce/open/as.html>
which is meant to run on a server costs $2499.00 a price I cannot 
afford. Could you please tell me what the simplest and best tools for 
this job would be. Could I run the low cost version on a desk top that 
will operate as a proxy? Thank you

George