missing contacts after reset and cloud restore
before backing up to cloud I had 55 contacts. After doing a reset and restore I had 20 (only my yahoo contacts). The contacts that remain seem to be my yahoo contacts
iPad 2, iOS 5.0.1
As a follow-on, you can read about iOS backups here:
Backups on Computer: http://support.apple.com/kb/HT4946
Backups to iCloud: http://support.apple.com/kb/HT4859
Note that in the section on "iTunes will backup the following information" in the 1st article, Contacts have an asterisk* next to them. Apple is telling you that your backup contains only some aspects of your Contacts:
* Your contacts are part of the backup to preserve recent calls and favorites lists.
They go on to say that you need to use some other means to backup your Contacts, such as iCloud. If you read between the lines, what they're saying is that non-Exchange Contacts can be created as iCloud (i.e. "me.com") Contacts so that they are backed up. That does not mean that you should use iCloud to store your Exchange accounts, that's completely unnecessary.
So, if you want to add new contacts directly to your device, it is best to associate them with an Exchange-type account so that they are backed up somewhere. That might be Yahoo, iCloud, or GMail (if set up as an Exchange account). Otherwise, such contacts are not part of any backup and subject to loss after a restore.