Is there anything I should watch out for providers on BP? I'm a newbie who needs references so I want to get some off BP but what should I be alert of that could be potential LE?

There are some providers who are newbie-friendly but require additional screening information about you.

Also, when using references, providers won't accept a reference if she is not established or known.
Many backpage providers don't have reviews and aren't established or stable.

In some places, BP  ads are ok,  I know some very good providers that use it.  In my area, it is not so great.  If she ads on BP, and is a member here, her ref is good.  Check out Preferred411, they allow the providers that are members to indicate if they are newbie friendly.  As a newb, you should read the self help center here, and join one or more of the verification sites, like P411, DateCheck, or RoomService200.

Swim

If your objective is references, go with well-reviewed ladies here on TER.