If you want to access your content from icloud you can download iDisk from apple store on your iphone. To log in, if you had a mobile me account, log onto mobile me at www.me.com and on the right hand side click on swith to iCloud and the transfer will be very smooth and easy. Then login using the same credential than mobile me. If you dn't have all of that, just create an iCloud account on www.icloud.com and when you have install iDisk from apple store login with your iCloud credential and you'll access everything from your iPhone.
To deduplicate your contact, you have to do it first on your adress book. Click on 'View' then 'Look for duplicate' and then choose to merge or select manually which contacts you want to merge or delete.
Hope this answers your questions
PS: For some reason, I have noticed recently that deduplicate have encounter some little problem on Lion OS...Adress Book don't seem to find duplicate when they are obviously displayed in front of me...strange! If this happen to you, create a thread on the community forum as I try to find an answer as well