Hi Playinpearls,
Tim's link is spot on in regards to setting up LDAP auth. The only thing from that link that I would tweak is how to test the solution. You can run a "aaa test-server" from the CLI. Or, in the GUI, you can go to the following:
Diagnostics > Network > AAA Test Server
Server Name > "Select your LDAP server"
Authentication Method > PAP
The GUI will prevent you from placing your username and password in cleartext on the CLI
-Mike