You could do an agency.... Or there's plenty of Indies who have specific experience for first timers. A quick search on the forum will reveal a number of options
Olivia Hartley (independent) would also be a great choice for a first timer. But I would second the choice of SweetVIPs. Harvi or any of the phone ladies will help.
Olivia Hartley and Danica Summers are my ATFs. Both are super beautiful, friendly, and caring brunettes. Danica is the best for a budget, a quick visit, quick booking, and less pre booking time, but I really love and recommend both!
Would second this, I've had a lot of luck booking with her on fairly short notice. She's always been very accommodating which helps as my work schedule tends to be a bit unpredictable.
At the risk of derailing the tread: I dunno if anyone else noticed but her last LL ad indicated she's going to be gone after the 24th. If you're hoping to see her, sooner might be better than later.