It's all a matter of preference. Date Check has a nice gallery search option. You can also get a lady to "sponsor" you on Date Check and get a few months for free.
Either P411 or Date Check should get you started.
Be respectful when communicating, do not EVER talk about money or sexual comments over the phone or through email. Here's a suggestion on how to communicate by email:
Real name and contact information.
Date-Check/P411 info and TER info.
Where you found them.
Date, time requested, length of appointment.
A couple of recent references when you get them.
Since you don't have the references, let them know upfront it's your first rodeo.
Depending on the person and their schedule, it may take up to 24 hours to get a response, so don't expect it to be like Domino's Pizza when the urge strikes you.
Don't be terribly upset if she asks for additional information, such as your employment. Remember, before you get too upset about "your privacy", you are wanting to invade "her privacy".
Be safe and have fun