You mentioned you had them saved to your pc and now you have a mac. Did you try to use the windows icloud tool (I haven't personally) not sure if it has the ability to pull your contacts and pipe them to the cloud.
It's a bit of work IMHO if you start out with like outlook and then move to a mac in regards to syncing your contacts or anything really.
You could try to get your contacts on your phone from your pc. Then in iTunes when you sync up to your MBP check the summary page and enabled syncing of contacts so they populate in your address book on your MBP.
Make sure your iCloud settings on both MBP and iPhone are set to sync contacts in cloud and both 'SHOULD' sync them up.