how do i retrive my ipad password?

Is your iPad under warranty?

Device not recognised in iTunes for Windows/Mac

Firstly, make sure that your device is not hidden (left hand pane). If it just reads device then toggle between SHOW and HIDE.

Secondly, try all the other ports on your computer, even a number of times.

Thirdly, if you have another computer try plugging your device into it without taking any action, give it a moment, remove it and try it back in your other computer again.

Failing all that, see here - http://support.apple.com/kb/TS1538 for Windows and http://support.apple.com/kb/TS1591 for Macs

Wrong passcode / Disabled

See here - http://support.apple.com/kb/HT1212

You will have to go down the route of a Restore. Please read carefully the links therein with regard to using a different different computer from that with which you normally sync.

[You may also have to put your device into Recovery Mode - http://support.apple.com/kb/HT1808 ]

Right on the bottom of Alan's post is what you want. Any forgotten password or locked iPad MUST be thrown into recovery and restored. The iPad won't let you do anything to it even in iTunes when there is a password on it. If the password is just acting up, restoring it should fix any software issues.

Throw into recovery, restore it. Unfortunately there is no other way