Advice on tutorials

[Wareagle]

i am looking for layer 4 switching equivalent

current deployment:

8 ip's on t-1, unmanaged switch, router for webservers 2, radius server 1, apps server 1, ( not the best setup but works for now). wifi router that provides customers on inside lan, webservice to the outside world. (Junk Hardware) needs to be replaced.
in this appliance i have client auth, rate limiting, usage tracking, vpn, does not work.
but need to pass wan ip's to customer on inside lan, which i can not do right now.

i am looking for a tutorial or a couple of them that i can basically build a switch for my needs. i have two servers to use to do this but need advice on
software to use and tute's. would like to tie everything together in one package.

can one of you expert guru's help.

thank you in advance.