If you can't find what you are looking for in LA, then you may be a tad too picky.

But seriously, how can you expect anyone else - especially on a national board such as this one - to do your leg-work for you?

Try using the 'search reviews' feature.
Try posting a more specific request on the LA Regional Board (over on the left hand side).
Try scanning the profile of the provider that you saw and enjoyed.  Cross-check the history of the other guys that have reviewed her highly.  If you can find someone else that they saw and rated highly, there is a good chance that you might also like to see her.

Finally, in your last sentence you asked for a reference to a provider "that will guarantee [you] a great time."  Ain't gonna happen.  As in everything else in life, there are no guarantees.  You do your best to maximize your potential for satisfaction, then present yourself well during your time with a lady.  Then hope for the best.

It's really not that hard to figure out.  I managed to do it.

With your level of experience, only see well reviewed ladies.  Assuming you have VIP, read the reviews and not just scan the profiles.