When I look at my profile, in the section where you can add your games, I have found that it will not let me add any Wii U games. Most games do not show up in the search (not even MK8), and when one does show up (like Nintendo Land) it will only let me Track or add to Wish List, but nothing else. Is this normal? Does anyone else have this issue?

It works for me. :S

Everyone has this issue.

Message the site admin ioi, if enough people complain maybe he'll do something. I've been bugging him for months, and he just won't spare the time, nor give me the power to fix this issue.

The only way to add some of these buggy games (not limited to WiiU) is to track them, and then from your tracked games select add. I wish I could permanently fix this issue, but I cannot.

but do the games even exist in the database?  many didn't use to.  I haven't tried in a long time, because after several attempts they weren't listed

My recommendation to you is to use a different website to keep track of the games you own. The feature has been broken on this site for some time and it is not going to be fixed.

They do exist, but the 'Database' isn't here anymore. In Dec. 2011 he basically locked the DB on here and started developing Gamewise. Everyone's game collection from old VGC and the gamr brands (I assume you know about this) is on there now. I do know that the Database on there is linked to VGC somehow, but adding games on here still does nothing, like you said. 

Track them here or on Gamewise? 

Also how do you add games to the database? 

How does one track a game?

It's cuz Wii U haz no games

I started using GameFAQs, their database is amazing. You even get recommendations for games you don't own based on other people with similar collections.

on VGC.

Go to My Games then type the game you want to add. If My Games is not an option, select Tracked. Just beside the add game bar you have options for My Games, Tracked and Wishlist. Select Tracked and then the game you tracked should be there. Beside the game there will be an option to Add the game to your collection. Select that and viola.

This only workds for games that appear in the add game search bar, so no Pikmin 3 for WiiU and no Destiny.

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As for adding games to the database, if you add a game on Gamewise it appears here most of the time. Too lazy to explain how to do that step by step, but basically at the top of Gamewise you go to Games I think and then add game. You then send a request to add a game. Within about 48 hours the game should appear on Gamewise. You then need to add a NTSC (North American) release date and once you do, the game will appear on VGC after another 24 hours.

I used to add games to the Gamewise database, but after a few months of ioi refusing to fix a fundamental flaw with VGC, I gave up. Even when I asked him directly to fix issues, he rarely did so. He abandoned VGC.

Above