Firstly you are talking about two separate network services which a SP can have loaded for you on your package. They may be mandatory or optional and they may have additional charges depending on the package. They may not allow the service on certain packages. Depends on the Network. The two services are sometimes referred to as CLIP and CLUR. CLIP stands for Call Line ID Presentation. CLIR - Call Line ID Restriction.
Basically you need to have CLIP activated on your phone to identify incoming calls. But a person can still prevent there number from showing if they wish by using CLIR on all or just some of their calls. So even if you have clip, if the call comes from someone who has activated CLIR there is nothing you can do. As for contacting the cellular company (your service provider) I doubt you will get much joy from the call centre. They will most likely only be able to tell you what numbers you have dialled out not what numbers have dialled in. For dialled in numbers you will need the Network itself and they are not just going to hand the info over. Unless you are paying for the call (Reverse billing) then they wont give it to you. If you do have to pay for received calls then it should be displayed as a on line item on your itemised invoice. If you have pre paid then you have even less chance of getting the number from either your SP or the network. Prepaid calls are not rated or stored.