A good source would be to check out department for insurance for the desired state; Click
here for Texas. Make sure the place you choose is certified/approved by the state prior to examination.
Now, I have been licensed (not for claims) in a few states. Up until this point, I have only attended in-person training classes. I will say overall that the classes are very generic and really provide methods of testing well, critical areas, and sample tests. Most classes prepare your for the examination only and not the career [which may be implied that your future agency/employer will].