I see you tried the usual solutions but they failed. I know of no step by step instructions for your tablet and PC. This is a shame but it can't be done since one persons machine is unlike the next.
I think it is time for you to call your local tech support and have them set it up.
I have a PC running Windows XP Pro. I have my itunes librabry on it. I also just recently bought a Samsung Galaxy 10.1 Wi-Fi tablet. I can not get itunes to sync. I have tried doubleTwist & iTunes Agent. I am no very techie savy so step by step instructions (with pics) would help.