cheers

Generally people message on here through the giveaways. Be careful messaging publicly on steam profiles, as Steam has a lot of auto bans for words like 'win', 'gift', and such. People like 'spacecat has visited' or something like that.

Also, there's fun things in the forums. Welcome to the site!

When your giveaway ends, the gift box "Giveaways Created" icon in the upper-right of every screen will light up. It's next to the [trophy-shaped] "Giveaways Won" and Messages icons. Click on the "Giveaways Created" icon and you should see a link under the Sent column to the page where the winner is listed. On that page is where you release the key to the winner (or where to find their Steamgifts page to get their Steam profile to Friend them if you're gifting that way)