Best Place To Find People For Idling Service

You can just make new steam account and idle cards yourself with ASF.

I can recommend ASF too. Get only the GitHub official releases, and that's safer than any deal you can make with most humans I know of.
https://github.com/JustArchiNET/ArchiSteamFarm/releases

It has a local html page for simple configuration. If you follow the install and configuration guide, it will be running in a matter of minutes - provided that you don't miss the fact that json files go in a folder called 'config', as I did >.<

You can also configure ASF for multiple accounts, and make them automatically send cards and items to your main account, redeem gifts and whatnot. It's a powerful tool.

Listen to the good advice, just idle them yourselves. :) Also, go back in time a month so you'll be able to do all the Winter Sale crap on that new account too. :)

You'll need to spend $5 to make the account unlimited, by redeeming a $5 physical wallet code on that account for example. Note: don't send your new account $5 via https://store.steampowered.com/digitalgiftcards/selectgiftcard - that doesn't work.

After you do that, either gift yourself some cheap games, buy sacks of gems for your main account, that one trading card you need for your main account, whatever. You don't want to leave a single cent behind - after a year of not using the store the market will be disabled and any leftover balance will be mocking you forever. :(

Do everything in https://steamcommunity.com/my/badges/2 for 500 free XP. Ideally you'll want to get up to level 10, so keep watching during the year for random events that grant free badges. And keep adding any leftovers from bundles or freebies from Humble Bundle.

Add all the free games that drop cards. I don't remember which ones, it's not a big list though. :)

Idle master or whatever should still work, but nowadays all the card idling fiends use ASF. It's much more complicated, and for idling a single game it's massively overkill, but it's a powerful tool...

Well, SteamTrades is the only place left that still has card idlers offering their services and still maintain some degree of trustworthiness…