Where do I buy games to give away here

There are a large number of stores (both legit and not so legit) where you can get keys, use this site to check authorized stores.

You can search a game and it will let you know where it is being sold, isthereanydeal

This is another similar website - gg.deals

Anything that sells (legit) Steam keys is good.
This link would be a good example. I modified it to list current deals that result in Steam keys.

As mentioned before, Is There Any Deal is a good place to check for places to buy the games, and they try to list only legit stores (so no grey markets, and you can report to the people responsible if you see something off regarding the stores listed on ITAD)
Just mind they don't list only Steam games, so pay attention to where the game is activated before going to the site of the deal to buy it

Personally, Humble, Fanatical and Indiegala are all I use beyond Steam itself.

https://www.steamgifts.com/discussion/Yd0M4/list-of-official-licensed-steam-retailersstores

List is a bit old but most of the stores still work.

you could try http://www.dailyindiegame.com/

I usually get Fanatical or Humble Bundles.
Or buy on Steam and purchase it as a gift (you need to add the winner to your friends list first).

Current bundles. You'll want to be aware of possible Region Locks on the games.
https://www.steamgifts.com/discussion/C0hpX/new-master-list-of-ongoing-steam-bundles

Thanks for the help guys I found a method that i think works for me. consider this thread closed :D