securing a website with sessions...

hi all i have been looking everywhere for an example of sessions that will fit my circumstances,,, we have a wholesale cd web site that at the moment is secured by a simple javascript thing but of course that is not very secure at all... what i want to be able to do is to have a login screen that the customer must fill out the first time they come and then that will write that session id etc to a mysql db and then the next time they come to any page i don't want them to have to enter a password etc , i just want it to read the cookie and let them in transparently... each customer of ours has a unique customer code that i would like to use as part of the login process... so they would enter their first name/last name/email/store name and customer code....the customer code would be validated against a table containing all of our customer codes... i know this is possible but i just can;t find a way to start..most examples are login/logout everytime senarios and i don't want that... can anyone help pls!! regards jason Regards Jason IT Manager Brisbane Australia